The Corporation of the TOWN OF MILTON

The Corporation of the TOWN OF MILTON Report To: Chair & Members of the Community Services Standing Committee From: Jennifer Reynolds, Director, Co...
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The Corporation of the TOWN OF MILTON Report To:

Chair & Members of the Community Services Standing Committee

From:

Jennifer Reynolds, Director, Community Services Paul Cripps, Director, Engineering Services

Date:

September 15, 2014

Report No:

COMS-025-14

Subject:

Urban Forest Management Strategy 2015-2024

Recommendation:

THAT the Town of Milton Urban Forest Management Strategy (UFMS) attached as Schedule A, prepared by Urban Forest Innovations Inc., be received for information; AND THAT the UFMS be used to guide staff with urban forest planning, implementation and management activity, subject to consideration of future Capital and Operating Budgets and Forecasts;

EXECUTIVE SUMMARY The beauty of Milton’s urban forest can be found in its many woodlots, parks, streetscapes and natural open space areas. Like many other communities, residents benefit from this natural asset in so many ways. The goal of the Urban Forestry Management Strategy (UFMS) was to develop a strategy for the Town as a resource to educate and inform how to manage the urban forest. The UFMS is a guiding document that outlines a Milton-centred approach to plan, care and enhance the Town’s urban forest during the next 10 years. The Strategy includes discussion on all the key subjects of urban forestry, including best practices for care and management. It also provides an understanding of the Town’s existing resources and practices to manage the urban forest. The Recommendations have been proposed with an awareness of the opportunities and challenges that affect Milton. Recognizing that the urban forest is a living asset that requires ongoing planning and management, the UFMS recommends that the Town consider implementing a strategic, proactive approach to manage and support the urban forest. The Recommendations act as a framework of the steps to consider to ensure that Milton’s community benefits from its urban forest for many years to come.

The Corporation of the TOWN OF MILTON

Report #: COMS-025-14 Page 2 of 4

REPORT Background In 2011, the Urban Forestry Pilot Project commenced with the goal of reviewing current practices and potential improvement opportunities within the Town’s service delivery of its urban forest. This Project recognized that the Town’s urban forest is a valuable community asset for current and future residents. Managing the urban forest includes all aspects of planning, design, and care and therefore the Urban Forest Steering Committee (UFSC) formed as part of this Project consisted of staff representatives from various departments. The UFSC met bi-monthly for a one-year term. The goal of the committee was to gain a better understanding of both the urban forestry related processes and also, the involvement of staff from various Town departments and external agencies in the urban forest portfolio. The approach was to outline all of the tree-related activities comprising the life cycle of municipal trees; in essence, the UFSC conducted a “cradle to grave” review of all stages ranging from planning and planting, to care, maintenance and replacement. This information was used in the preparation of the Terms of Reference for the Urban Forestry Management Strategy. In 2012, Urban Forest Innovations Inc. commenced their project with the Town. Discussion With challenges such as climate change, ice storms, Emerald Ash Borer, and other impacts affecting our trees, woodlots and natural areas, the value of our trees and the urban forest is increasingly gaining public attention and interest. Where once trees may have been considered a part of the municipal landscape requiring minimal management or care, there is information and research identifying that the urban forest is a dynamic ecosystem susceptible to various threats such as ice storms, pests, and even site (soil and cultural) conditions. These threats to our trees, if not proactively managed or mitigated, could prove to be problematic, expensive and detrimental to providing a healthy urban forest. At the same time, municipalities are often faced with a range of pressures on their funding and human resources. The UFMS is a comprehensive document that focuses on understanding, caring, growing, planning and supporting Milton’s urban forest with a focus on an active management approach. For each of these subject areas, the consulting team reviewed and provided information on the current status, best management practices and precedents, and opportunities for improvement. The final report includes the following chapters: • Responding to Challenges: Strategic Urban Forest Management Planning

The Corporation of the TOWN OF MILTON • • • • •

Report #: COMS-025-14 Page 3 of 4

Setting the Direction (Policy to Support Strategy, Vision, Guiding Principles, Strategic Objectives) Current Status of Urban Forestry in the Town of Milton Best Practices and Precedents Opportunities for Improvement Conclusion, Recommendations and Financial Impact

The UFMS proposes 17 Recommendations which are prioritized as high, medium and low for the Town’s consideration. Relationship to the Strategic Plan A responsible cost-effective and accountable local government. Direction 1 – Establish priorities that support the municipal service requirements of the majority of local residents. Direction 2 – Engage in transparent and accountable decision-making process and actions. Direction 3 – Properly fund municipal services and community infrastructure through a combination of fiscally responsible operating budgets, capital budgets, effective reserves and reserve fund management. Direction 4 – Demonstrate leadership in matters that affect Milton. Well managed growth, well planned spaces. Direction 3 - Encourage cost effective and timely municipal/community infrastructure development. Direction 4 – Encourage well timed service delivery. A safe, livable and healthy community. Direction 2 – Maximize community safety and security. Direction 3 – Protect and enhance our heritage identity and character. A thriving natural environment that is a valued community asset to be protected, maintained and enjoyed. Direction 1 – Protect and enhance natural features. Direction 2 – Encourage new development to be integrated with the natural environment. Direction 3 – Promote the enjoyment and responsible use of natural areas. Financial Impact There is no direct financial impact as a result of this Strategy. Implementation of the Urban Forestry Management Strategy will be addressed and considered by Milton Council through the annual operating and capital budget process, with consideration for all other Town of Milton budget priorities.

Report #: COMS-025-14 Page 4 of 4

The Corporation of the TOWN OF MILTON Respectfully submitted, Jennifer Reynolds Director, Community Services Paul Cripps, P. Eng. Director, Engineering Services For questions, please contact: Paul Cripps, Director, Engineering Services or Jon Meyer, Coordinator, Parks Planning

ext. 2501 or ext. 2572

Attachments Schedule A: Urban Forest Management Strategy 2015 – 2024 This document is available in an accessible format upon request CAO Approval William Mann, MCIP, RPP, OALA, CSLA, MCIF, RPF Chief Administrative Officer

COMS-025-14 Schedule A

Town of Milton, Ontario

URBAN FORESTRY MANAGEMENT STRATEGY 2015-2024

FINAL

Acknowledgements Town of Milton Urban Forest Steering Committee (UFSC) The Town of Milton Urban Forest Management Strategy was developed with the input and support of the Town’s multi-departmental Urban Forest Steering Committee. Committee members included: Roberta Sager, Manager, Parks Planning, Community Service Department Lisa VanderVliet, Coordinator, Parks Design and Development, Community Services Department Jon Meyer, Coordinator, Parks Planning, Community Services Department John Brophy, Senior Manager, Infrastructure, Engineering Services Department Martin Bateson, Senior Manager, Development Engineering, Engineering Services Department Jim Cartwright, Acting Manager, Operations, Engineering Services Department Doug Thompson, Manager, Operations, Engineering Services Department (ret.) Sheryl Hill, Senior Manager, Finance, Corporate Services Department Stephanie Jarvis, Environmental Planner, Planning Policy and Urban Design, Planning and Development Department

Town of Milton Senior Management Team Jennifer Reynolds, Director of Community Services Paul Cripps, Director of Engineering Services Barbara Koopmans, Director of Planning and Development Linda Leeds, Director of Corporate Services

Urban Forest Management Strategy Consulting Team Philip van Wassenaer, Urban Forest Innovations Inc. Alex Satel, Urban Forest Innovations Inc. Margot Ursic, Beacon Environmental Ltd. Dr. W. Andy Kenney (Sr. Urban Forestry Advisor), Urban Forest Innovations Inc. Town of Milton Urban Forestry Management Strategy

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Executive Summary This document presents a 10-year Urban Forest Management Strategy (UFMS) for the Town of Milton. Situated at the foot of the ancient Niagara Escarpment, the Town of Milton is Canada’s fastest-growing municipality. The Town’s residents, both established and new, enjoy a high quality of life in a healthy, vibrant and prosperous community. Some of the most important contributors to this high quality of life are the Town’s trees – its urban forest. The development and implementation of a strategic plan to manage the Town’s urban forest is timely and responds to the numerous challenges impacting the Town’s street, park and forest trees currently and in the coming years. Urban Forest Benefits Urban forests provide wide-ranging benefits to urban residents. Notably, larger and older trees provide exponentially more of these benefits than smaller ones. Trees provide numerous environmental, economic and social (community and health) benefits. Together, such benefits contribute significantly to making Milton a more sustainable and livable community. Some of the many benefits urban trees provide include: • • • • • • • • • •

Cleaning the air Improving stream water quality Ameliorating urban climates and mitigating climate change through carbon storage Reducing energy use and associated costs Providing habitat for urban wildlife such as mammals, birds, and even fish. Increasing property values Stimulating economic activity Reducing exposure to ultraviolet radiation and extreme heat by providing shade and cooling Improving human health by providing settings for physical activity and reducing exposure to certain environmental risks such as pollutants Building stronger communities by providing settings for social interactions

Recent studies have shown that exposure to treed and natural areas can improve recovery after surgery, reduce stress and improve learning and creativity. They have also documented reductions in property crimes in residential areas with street trees and vegetation, and 5% to 20% decreases in motor vehicle accidents on roads with trees on the roadsides. Many of these community and health benefits cannot be monetized, and therefore cannot be included in a traditional cost-benefit analysis of urban forest management. However, their contributions to making the Town of Milton a desirable and livable community are immense.

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Challenges to Urban Forest Sustainability There are many potential challenges to the health and sustainability of Milton’s urban forest. These include, among many: Downtown Milton has been identified as an “Urban Growth Centre” in the Province’s Growth Plan for the Greater Golden Horseshoe (2006). Other parts of the Town are also expected to continue experiencing rapid population growth. The current population of 95,879 is expected to grow to 161,750 by 2021 – an increase of nearly 200% above the 2006 population. While new residents will bring diversity and opportunities, this population growth will also increase demand for housing and place pressure on the Town’s grey infrastructure (e.g., roadways, water servicing) and green infrastructure (e.g., trees, parks and natural areas). These pressures, combined with other present and emerging threats such as pests and diseases, climate change, and competition for resources, will require long-term planning, active management, ongoing monitoring, and creative problem solving to sustain the urban forest as a healthy and growing part of the community. Estimates for the average lifespan of an urban tree vary widely, but most range from just 7 to 30 years. A number of factors can reduce tree longevity, including: • • • • • • • • •

Limited post-planting care and maintenance of young trees Pests, pathogens and diseases, which disproportionately affect stressed urban trees Competition by invasive species Inadequate soil volume and quality to sustain large, healthy trees Competition for above- and below-ground space with other municipal infrastructure Land use change and pressure from competing land uses Limited financial and human resources for urban forest monitoring and maintenance Lack of public awareness, engagement and support in urban forest stewardship activities Climate change and extreme weather events

Vision The vision for Milton’s urban forest, to be realized through the implementation of this Urban Forest Management Strategy, is presented below: The Town of Milton values its urban forest for the environmental, economic, community and health benefits it provides to its community. The Town recognizes the value of this community asset in its planning and our day-to-day operations. This asset is sustained by the Town as it works towards proactive management and enhanced stewardship and partnerships in support of its urban forest.

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Guiding Principles The following principles have guided the development of this urban forest management strategy, and are also intended to guide its implementation. 1. Develop a better understanding of the urban forest to support more effective management. 2. Plant the right tree in the right place with adequate soil volume and quality to reduce infrastructure conflict, the spread of invasive species, poor tree health and tree-related risk. 3. Implement more proactive tree management to achieve a healthier urban forest, a more livable community, and reduced urban forest management costs over time. 4. Recognize trees as essential municipal green infrastructure to ensure that they are planned for, maintained, and replaced as required. 5. Implement an active adaptive management approach to ensure that the Town is able to effectively respond to new challenges, implement new techniques, and benefit from developments in the field of urban forestry. 6. Engage the local community in stewardship and support of the urban forest to achieve the vision and objectives of this Strategy. Strategic Objectives The Town of Milton seeks to achieve the following objectives though the implementation of this strategy over its 10-year planning horizon. 1. Allocate adequate human, financial and operational resources dedicated to urban forest maintenance, monitoring and planning; 2. Increase the proportion of proactive urban forest management and reduce the amount of reactive management needed;Increase urban forest structural and species diversity, and increase the number of native, non-invasive tree species tolerant of urban forest stressors such as climate change, pests and diseases; 3. Acknowledge the importance of the urban forest in future high-level planning documents, and create and implement policies that support its protection and enhancement; 4. Expand the knowledge base about current conditions of the Town’s urban forest; 5. Increase awareness among Town residents, staff and representatives about the wide range of benefits provided by the urban forest, and about how to manage it to ensure its long-term sustainability, and;

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6. Expand stewardship initiatives, increase community engagement, and develop more partnerships that support the urban forest. Responding to the Challenges Strategic urban forest management planning has been adopted by a number of municipalities across North America and beyond as a tool to address many of the same challenges as experienced by Milton’s urban forest. The primary purpose of this Urban Forest Management Strategy is to identify the most effective ways to coordinate policies, practices and procedures pertaining to all tree-related activities undertaken by the Town of Milton and to improve the Town’s ability to manage the urban forest in a proactive manner. While this plan is primarily intended for use by Town staff, it is also meant to be an accessible resource for all stakeholders and Milton’s residents. By pursuing the various strategies and best practices outlined within the plan, individuals and groups of all kinds will be able to work together towards improving and expanding Milton’s urban forest. Although this strategy is focused on a 10-year planning horizon, active adaptive management will ensure that it carries on as a ‘living document’ well beyond that time frame. This is achieved, in part, through a multi-part planning framework that is divided into three tiers, as well as a built-in periodic review cycle. • • •

Tier 1: 10-year Strategy (2015-2024) (this document) Tier 2: Five-year Management Plans (2015-2019 and 2020-2024) (to be developed) Tier 3: Annual Operating Plans (to be developed)

Forested ecosystems are complex dynamic entities, particularly with the addition of a human element. Those involved in urban forest management cannot always predict the changes or events, such as severe weather, pest infestations or changes to resource allocation priorities that may impact the ability to achieve urban forest sustainability. For this reason, the concept of active adaptive management is firmly embedded in this urban forest management strategy. Strategy Content This Strategy addresses relevant issues under five topic areas: •

• • • •

Understanding the Urban Forest, which reviews the existing tree inventory, considers strategies for improving the Town’s understanding of its urban forest resource, and explores opportunities to integrate trees into an effective asset management system; Caring for the Urban Forest, which reviews the implementation of urban forest health, maintenance and risk management in the Town; Growing the Urban Forest, which reviews tree establishment practices and programs; Planning the Urban Forest, which examines relevant legislation, policies and guidelines and explores how planning tools can promote urban forest sustainability, and; Supporting the Urban Forest, which focuses on opportunities for community and stakeholder engagement, stewardship and partnership.

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For each of the five topic areas, the strategy considers: • • •

The Current Status of practices and policies implemented by the Town; Best Management Practices and Precedents from the technical and scientific literature, and from comparable municipalities within North America, and; Opportunities for Improvement of Milton’s urban forest management program, based on a ‘gap analysis’ considering current and best practices, and focusing on actions that are practical and costeffective.

Recommended action items have been developed based on careful consideration for identified opportunities for improvement under each topic area, and on extensive consultation with Town staff. They are presented in Section 7 with target timelines, estimated resource requirements, potential partners, and related goals that they support. Summary of Recommendations High Priority Recommendations Recommendation 1: Continue to implement the adaptive Emerald Ash Borer (EAB) management strategy as per Council Report No. ENG 028-13. Recommendation 2: Review staffing resources available for urban forest program administration and management (potential implementation options below). • Option A: Retain an Urban Forestry professional on a contracted basis to implement high priority projects • Option B: Create a new Urban Forestry professional position, Engineering Services Department • Option C: Retain Urban Forestry professional on contracted basis until 2016, then as part of successional and/or staff resource realignment create a potential Road and Urban Forestry Operations professional position by 2017 • Option D: Create 2 Annual - 4 Month Seasonal Maintenance Operational Personnel (SMOP) positions dedicated to urban forestry • Option E: Review existing staff resources and consider reprioritization or realignment of duties, secondment of staff to special projects, or utilization of staff working groups. Recommendation 3: Investigate and implement a Tree Risk Management Strategy which includes a Priority Tree Risk Assessment.

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Medium Priority Recommendations Recommendation 4: Implement a comprehensive young tree establishment and maintenance program. Recommendation 5: Require scheduled young tree maintenance prior to acceptance of plant material in new developments (developments both by Developers and the Town). Recommendation 6: Consider the development of a Tree Protection Policy for Town-owned trees and implement existing and new tree protection standards during development. Recommendation 7: Investigate and utilize Terms of Reference for both tree inventory and tree management plans for woodlots/woodlands to be assumed by Town through any planning and development processes. Recommendation 8: Update all urban forest maintenance contracts to be consistent with best management practices and industry standards, in accordance with a Council-approved Level of Service. Recommendation 9: Update Engineering and Parks Standards Manual to be consistent with current best management practices and industry standards, in accordance with a Council-approved Level of Service. Recommendation 10: Establish and implement an appropriate Level of Service (including pruning cycle) for publicly-owned street/boulevard trees with consideration of current best management practices and industry standards. Recommendation 11: Investigate options to improve and expand the existing Town-owned tree inventory and implement a tree asset management system. Recommendation 12: Expand promotion, outreach and education about urban forestry to the public and other stakeholders. Recommendation 13: Establish an ad hoc urban forestry working group. Low Priority Recommendations Recommendation 14: Support and implement community-based tree-related events and develop volunteer network. Recommendation 15: Recognize the value and functions of the Urban Forest in relevant Town strategies, policies and the Official Plan, when revised, and use consistent terminology Town-wide. Recommendation 16: Pursue partnerships with agencies and organizations to expand urban forest stewardship activities. Recommendation 17: Investigate criteria for identification of heritage trees and explore the potential for a Heritage Tree Register.

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Contents Executive Summary....................................................................................................................................... ii List of Figures ............................................................................................................................................... xi List of Tables ................................................................................................................................................ xi 1.

Introduction .......................................................................................................................................... 1 1.1. Milton’s Urban Forest ................................................................................................................... 1 1.2. The Value of the Urban Forest ...................................................................................................... 3 1.2.1. Environmental Benefits......................................................................................................... 3 1.2.2. Economic Benefits................................................................................................................. 5 1.2.3. Community and Health Benefits ........................................................................................... 5 1.2.4. Climate Change Adaptation and Mitigation ......................................................................... 5 1.3. Threats and Challenges ................................................................................................................. 6 2. Responding to the Challenges: Strategic Urban Forest Management Planning ................................... 7 2.1. Plan Structure and Implementation ............................................................................................. 8 2.1.1. Three-tier Structure .............................................................................................................. 8 2.1.2. Active Adaptive Management............................................................................................... 9 2.1.3. Strategy Review and Monitoring .......................................................................................... 9 2.1.4. Strategy Content ................................................................................................................. 10 3. Setting the Direction ........................................................................................................................... 11 3.1. Policy Support for this Strategy .................................................................................................. 11 3.2. Vision........................................................................................................................................... 11 3.3. Guiding Principles ....................................................................................................................... 11 3.4. Strategic Objectives .................................................................................................................... 12 4. Current Status of Urban Forestry in the Town of Milton .................................................................... 13 4.1. Understanding the Urban Forest: Tree Inventory and Asset Management ............................... 13 4.1.1. Importance of a Tree Inventory and Asset Management System ...................................... 13 4.1.2. Milton’s Existing Tree Inventory ......................................................................................... 13 4.2. Caring for the Urban Forest: Tree Maintenance, Risk Management and Urban Forest Health . 17 4.2.1. Urban Forest Program Administration................................................................................ 17 4.2.2. Urban Tree Maintenance – Public Trees............................................................................. 18 4.2.3. Urban Tree Maintenance – Mature Trees .......................................................................... 19 4.2.4. Urban Tree Maintenance –Newly Planted Trees ................................................................ 19 4.2.5. Urban Tree Maintenance - Tree Risk Management............................................................ 19 4.2.6. Urban Forest Health Management - Overview ................................................................... 20 4.2.7. Urban Forest Health Management – Pest and Disease Management (General) ............... 21 4.2.8. Urban Forest Health Management – Emerald Ash Borer ................................................... 22 4.2.9. Urban Forest Health Management – Trees in New Developments .................................... 22 4.2.10. Urban Forest Health Management – Tree Protection ........................................................ 23

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4.3. Growing the Urban Forest: Tree Establishment ......................................................................... 25 4.3.1. Tree Establishment –Development..................................................................................... 26 4.3.2. Tree Establishment – Infill, Replacement and Capital Projects .......................................... 27 4.4. Planning for the Urban Forest: Policies, By-laws and Guidelines ............................................... 28 4.4.1. Town of Milton – Town-wide Strategies and Plans ............................................................ 28 4.4.2. By-laws and Related Legislation.......................................................................................... 30 4.4.3. Town Guidelines and Standards ......................................................................................... 32 4.4.4. Halton Region...................................................................................................................... 32 4.5. Supporting the Urban Forest: Education, Outreach and Stewardship ....................................... 34 4.5.1. Town of Milton.................................................................................................................... 34 4.5.2. Halton Region...................................................................................................................... 36 4.5.3. Conservation Halton ........................................................................................................... 37 4.5.4. Other Potential Partners and Funding Sources .................................................................. 37 5. Best Practices and Precedents ............................................................................................................ 39 5.1. Understanding the Urban Forest: Tree Inventory and Asset Management ............................... 39 5.1.1. Tree Inventories .................................................................................................................. 39 5.1.2. Examples of Successful Tree Inventories ............................................................................ 42 5.1.3. Urban Forest Asset Management ....................................................................................... 43 5.1.4. Canopy Cover Assessment .................................................................................................. 44 5.2. Caring for the Urban Forest ........................................................................................................ 45 5.2.1. Departmental Coordination ................................................................................................ 45 5.2.2. Service Delivery ................................................................................................................... 45 5.2.3. Proactive Maintenance of Publicly-owned Trees ............................................................... 46 5.2.4. Young Tree Maintenance .................................................................................................... 46 5.2.5. Tree Risk Management ....................................................................................................... 47 5.2.6. Pest and Disease Management........................................................................................... 48 5.2.7. Pest and Disease Management - Components of an Emerald Ash Borer Strategy ............ 49 5.2.8. Emerald Ash Borer Management in Other Jurisdictions..................................................... 52 5.2.9. Tree Protection ................................................................................................................... 54 5.3. Growing the Urban Forest .......................................................................................................... 62 5.3.1. Tree Species Selection......................................................................................................... 62 5.3.2. Nursery Stock Size and Quality ........................................................................................... 62 5.3.3. Resident Request Programs ................................................................................................ 63 5.3.4. Development Tree Planting ................................................................................................ 63 5.3.5. Tree Growing Environment and Setbacks........................................................................... 65 5.3.6. Enhanced Rooting Environments ........................................................................................ 66 5.4. Planning for the Urban Forest..................................................................................................... 67 5.4.1. Recognizing the Urban Forest through Strategic and Official Plans ................................... 67 5.4.2. Policies, By-laws and Guidelines to Support the Urban Forest........................................... 69 5.5. Supporting the Urban Forest ...................................................................................................... 72 5.5.1. Examples of Outreach and Stewardship in Comparable Municipalities ............................. 72 5.5.2. Examples of Effective Partnerships in Other Municipalities ............................................... 73 Town of Milton Urban Forestry Management Strategy

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6.

Opportunities for Improvement ......................................................................................................... 75 6.1. Understanding the Urban Forest ................................................................................................ 75 6.1.1. Opportunities for Improvement of the Tree Inventory and Tree Asset Management....... 75 6.2. Caring for the Urban Forest ........................................................................................................ 77 6.2.1. Opportunities for Improvement of Urban Forest Program Administration ....................... 77 6.2.2. Opportunities for Improvement of Urban Tree Maintenance............................................ 79 6.2.3. Opportunities for Improvement of Urban Tree Risk Management .................................... 82 6.2.4. Opportunities for Improvement of Urban Forest Health Management ............................. 82 6.2.5. Opportunities for Improvement of Tree Protection ........................................................... 83 6.3. Growing the Urban Forest .......................................................................................................... 83 6.3.1. Opportunities for Improvement of Tree Establishment ..................................................... 83 6.4. Planning for the Urban Forest..................................................................................................... 86 6.4.1. Making Terminology Consistent ......................................................................................... 86 6.4.2. Recognizing the Urban Forest through Strategic and Official Plans ................................... 86 6.4.3. Canopy Cover ...................................................................................................................... 87 6.4.4. Planning Process for Assuming Woodlots/Woodlands....................................................... 87 6.4.5. Policies, By-laws and Guidelines to Support the Urban Forest........................................... 88 6.5. Supporting the Urban Forest ...................................................................................................... 88 6.8.1. Opportunities for Education and Outreach ........................................................................ 89 6.8.2. Opportunities for Stewardship ........................................................................................... 89 6.8.3. Opportunities for Partnerships and Funding ...................................................................... 90 6.8.4. Outreach and Stewardship Opportunities to Consider in Future Strategies ...................... 90 7. Conclusion, Recommendations and Financial Impact ........................................................................ 91 7.1. Conclusion ................................................................................................................................... 91 7.2. Urban Forest Management Strategy Recommendations .......................................................... 92 7.2.1. Recommendations .............................................................................................................. 92 7.2.2. Opportunities to Consider in Future Strategies .................................................................. 92 7.2.3. Recommendations and Financial Impact ............................................................................ 93 8. References Cited ................................................................................................................................. 96 9. Glossary of Terms................................................................................................................................ 98

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List of Figures Figure 1: Map of the Town of Milton ............................................................................................................ 4 Figure 2: Structure of the Town of Milton Urban Forest Management Strategy and implementation. ...... 8 Figure 3: Example of data in 2009 Urban Milton street tree inventory. .................................................... 15 Figure 4: Diameter at breast height distribution of street trees in Urban Milton neighbourhoods .......... 15 Figure 5: Top ten tree species, eight ‘Urban Milton’ neighbourhoods....................................................... 16 Figure 6: Top seven tree genera (top 90%), eight ‘Urban Milton’ neighbourhoods .................................. 16 Figure 7: Informational door hangers for residents ................................................................................... 35 Figure 8: Map of upper and lower-tier jurisdictions in southern Ontario with private tree by-law .......... 70 Figure 9: Example engineering roadway cross-section............................................................................... 81

List of Tables Table 1: Summary of Milton’s urban forest health management activities (proactive and reactive)........ 21 Table 2: Tree protection guidelines in Town of Milton 2014 Parks and Engineering Standards Manual. . 24 Table 3: Attributes of varying levels of tree inventory. .............................................................................. 41 Table 4: Comparison of municipal Emerald Ash Borer management strategies in Ontario. ...................... 53 Table 5: Minimum Tree Protection Zones and Critical Root Zones, City of Burlington. ............................. 55 Table 6: Minimum Tree Protection Zones, Town of Oakville. .................................................................... 57 Table 7: Minimum Tree Protection Zones, City of Toronto. ....................................................................... 58 Table 8: Comparison of selected municipal tree protection procedures or policies.................................. 61 Table 9: Key aspects of development tree planting mechanisms and programs. ...................................... 64 Table 10: Sample tree growing environment requirements from 3 Ontario municipalities. ..................... 65 Table 11: Proposed young tree maintenance schedule for trees planted in new communities................ 85 Table 12: Town of Milton Urban Forest Management Strategy 2015-2024 Recommendations ............... 93 Table 13: Operating, Capital and UFMS proposed Net Financial Impact over next 5 years . .................... 95

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1.

Introduction

Situated at the foot of the ancient Niagara Escarpment, the Town of Milton is Canada’s fastest-growing municipality. The Town’s residents, both established and new, enjoy a high quality of life in a healthy, vibrant and prosperous community. Some of the most important contributors to this high quality of life are the Town’s trees – its urban forest. The urban forest is an integral part of the Town’s community fabric. Like parks and natural areas, trees are “green infrastructure” and are as important as roadways, power lines or drainage systems to maintaining a functioning, healthy and livable community. With fewer trees, vital ecological services such as clean air, water, and habitat connectivity are degraded, and fewer benefits are passed on to urban and suburban residents. The Town’s urban forest will face increasing challenges as Milton continues to grow. Now is the time to take action and to ensure that practices and policies are put in place that protect, establish and maintain urban trees well into the future. Long-term urban forest sustainability will benefit Milton and all of its residents, and will require a targeted and sustained investment if urban forest benefits are to be fully realized. Through this first ten-year Urban Forestry Management Strategy (2015 – 2024), the Town of Milton recognizes the value of its urban forest, and demonstrates its commitment to the continued and improved stewardship of this valuable asset. The actions outlined in this document will enable the Town to more effectively manage its existing trees, achieve greater success in tree establishment, and promote community awareness of the importance of trees in the Town, both on public and private lands over the next decade. While it considers all of the Town’s tree resources, this first Strategy primarily focuses on actions for the Town’s urban areas and Town-owned components, where the pressures on the urban forest are greatest. What is the urban forest? The term “urban forest” includes all the trees and shrubs within a given jurisdiction, as well as the ecological systems that sustain them. In the Town of Milton, this includes trees within the urban boundary (street and park trees, woodlots, open spaces, stormwater management ponds and channels, etc.), as well as treed areas in the Town’s rural areas and hamlets.

1.1. Milton’s Urban Forest In addition to its large rural area, the Town of Milton is home to several distinct urban land use types. Consequently, the character of the Town’s urban forest varies across its urban area. The residential streetscapes of Old Milton are home to some of the Town’s oldest and largest urban trees, while newer subdivision communities are generally populated with more recently-planted,

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younger trees. The Town’s industrial areas have relatively little tree cover, while some of the remnant woodlots and natural areas such as Livingston Park, in proximity to the urban area, retain many characteristics of natural forests. In 2009, the Town undertook an inventory of the species, diameter (size), condition and hazard potential of Town-owned street trees in eight of the Town’s established urban neighbourhoods. Inventory findings suggest that the species and genus diversity of the urban forest is relatively low, but that the majority of trees are in fair to good condition. The most common trees in this part of Milton are maple (genus Acer) and ash (genus Fraxinus), which together account for almost 65% of inventoried street trees (in the 2009 inventory area), and only 7 tree genera 1 make up 90%. This reliance on just a small selection of species is potentially problematic, especially considering the threat currently posed by the Emerald Ash Borer beetle, which will likely eliminate all untreated ash trees throughout the Town within the next 10 to 15 years, and will require the removal and replacement of thousands of Town-owned trees. More recently, tree establishment in newer communities and parks has included a more diverse range of tree species, such as tulip-tree, Kentucky coffee tree, and red and bur oaks. Over time, these plantings will contribute to a more diverse urban forest, provided that newly-planted trees are properly cared for and are able to reach their full maturity, thus providing wide-ranging urban forest benefits. The Town has not undertaken a canopy cover assessment, but based on existing mapping it is generally known that the majority of the Town’s tree cover is associated with the Escarpment and rural woodlands, while tree cover in the urban area is primarily associated with remnant woodlands and hedgerows, as well mature trees in the older parts of the Town. Like most of Southern Ontario, the area around present-day Milton was once largely covered in forest, which was progressively cleared for agriculture over the course of the 19th century. Based on the data from the recent subwatershed update for Sixteen Mile Creek Areas 2 and 7 (2010), the extent of woodland, (including treed wetlands and hedgerows) in formerly rural and urbanizing (Derry Green and Boyne Survey) areas is between 6% and 8% of the land cover, while the canopy cover in the Central Business District is estimated to be around 14%. This tree cover is likely greater than it was in the 19th century, when agricultural land uses dominated the landscape. Recognizing the importance of having trees and natural areas in the urban area, the Town has assumed ownership of 27 woodlots through the planning process that, in total, cover 59 ha. Although these woodlots are largely surrounded by residential and commercial development, in most cases Town parks have been created adjacent to these woodlots. This both enhances their ecological functions and better integrates the woodlots into the community. In addition, many areas of Milton have been recently developed and include new plantings which may mature over time and contribute to an increased and more broadly distributed tree canopy in the urban area.

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Genus (plural genera) is a taxonomic rank between family and species. In binomial nomenclature, the genus forms the first part of the species name for each individual species within a given genus. For example, the genus Acer (maple) contains all species of maple trees. Sugar maple, an individual species within the genus Acer, is named Acer saccharum.

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What is Urban Forestry? A specialized branch of forestry that has as its objectives the cultivation and management of trees for their present and potential contribution to the physiological, sociological and economic well-being of urban society. These contributions include the over-all ameliorating effect of trees on their environment, as well as their recreational and ... amenity value. - Erik Jorgensen, Canada’s first urban forester, defined the term in 1967

1.2. The Value of the Urban Forest Urban forests provide wide-ranging benefits to urban residents. There is an ever-increasing body of literature that conclusively demonstrates that trees in built-up areas provide important environmental, economic, community and human health benefits. Notably, larger and older trees provide exponentially more of these benefits than smaller ones. Trees have the capacity to clean the air and water, moderate the local climate, and provide many other environmental benefits. Trees also provide social and economic benefits ranging from contributing to mental and physical health to increasing the value of residential real estate. Together, such benefits contribute significantly to making Milton a more sustainable and livable community. While some benefits cannot be easily measured or ascribed a monetary value, recent research has developed effective methods to quantify the value of some environmental benefits provided by trees.

1.2.1. Environmental Benefits

Urban trees are critical components of the urban environment. Just some of the many important environmental benefits provided by the urban forest include: • • • • • • •

Cleaning the air, by binding airborne pollutants to leaf and bark surfaces (Cavanagh et al., 2009; Nowak et al., 2006) Improving stream water quality, by reducing surface runoff rates (Endreny, 2005; Xiao and McPherson, 2002) Reducing high urban temperatures, through shading and evapotranspiration (Akbari et al., 2001; Bowler et al., 2010a) Reducing the greenhouse effect, by storing and sequestering carbon (Brack, 2002; McHale et al., 2007) Reducing energy use, by shading buildings or sheltering them from cold winds (Donovan and Butry, 2009; Heisler, 1986) Conserving soil resources, by stabilising slopes and intercepting water (Endreny, 2005) Providing habitat for urban wildlife such as mammals, birds, and even fish (Faeth et al., 2011; Fernandez-Juricic, 2000)

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Figure 1: Map of the Town of Milton. Green box highlights area of 2009 “Urban Milton” street tree inventory.

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1.2.2. Economic Benefits

Although they are not generally grown for products that can be bought and sold, trees in urban forests are also good for the local economy. Studies have demonstrated that: • • •

The presence of larger trees in yards and streetscapes can add between 3% and 15% to the value of homes, even if the trees are on neighbouring properties (Wolf, 2007) Homes on wooded lots typically sell faster than comparable untreed properties (Donovan and Butry, 2010) Shoppers express a willingness to pay, on average, between 9% and 12% more for goods and services in well-treed business districts, and are also willing to travel longer distances to such areas. Once there, they will often spend more time browsing and shopping (Wolf, 2003).

Trees in rural areas can provide direct economic benefits through the harvesting of timber and nontimber forest products. At the end of their lifespans, even urban trees can become valuable and highlysought after wood products, or be used to nourish young trees as high-quality mulch.

1.2.3. Community and Health Benefits

Trees provide important community and human health benefits, particularly in urban areas where population densities are greater. These benefits range widely, and include: • • • • • • •

Reducing exposure to ultraviolet radiation and extreme heat by providing shade and cooling (Bowler et al., 2010b) Encouraging active living by providing settings for physical activity (Giles-Corti et al., 2005) Providing social settings that tend to reduce incidences of crime (Donovan and Prestemon, 2012; Kuo and Sullivan, 2001) Promoting human health by reducing exposure to certain environmental risks such as pollutants (Lovasi et al., 2008; Maher et al, 2013) Reducing mental fatigue by providing relaxing places or views (Tennessen and Cimprich, 1995) Building stronger communities by providing settings for social interactions (Coley et al., 1997) Increasing safety of community streets by calming traffic flow (Naderia et al., 2003)

Recent studies have shown that exposure to treed and natural areas can improve recovery after surgery, reduce stress and improve learning and creativity. They have also documented reductions in property crimes in residential areas with street trees and vegetation, and 5% to 20% decreases in motor vehicle accidents on roads with trees on the roadsides. Many of these community and health benefits cannot be monetized, and therefore cannot be included in a traditional cost-benefit analysis of urban forest management. However, their contributions to making the Town of Milton a desirable and livable community are immense.

1.2.4. Climate Change Adaptation and Mitigation

Among the most important benefits provided by a healthy urban forest are climate change adaptation and mitigation. By moderating local temperatures through shading and evapotranspiration, removing pollution from the air, and moderating storm water flows, Milton’s trees help the community adapt and be more resilient to climate change. Trees also sequester and store carbon, thereby reducing the

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concentrations of this significant greenhouse gas and potentially helping mitigate the impacts of climate change. Climate change presents one of the most pressing challenges for urban trees, some of which already suffer from non-climatic stressors such as competition for resources, soil compaction, drought, pests and diseases. Strategies to reduce the effects of climate change on the urban forest include strategies that also contribute to overall urban forest sustainability, as outlined below. • • • • •

Minimizing non-climate stressors such as impervious surfaces, invasive plant species or pests and diseases; Improving habitat for existing and newly-established trees to increase survival; Planting a diversity of tree species, including those better adapted to warmer and drier conditions; Developing and implementing a risk management and extreme weather response strategy; Protecting and enhancing natural areas connectivity to facilitate species movement and adaptation.

1.3. Threats and Challenges Downtown Milton has been identified as an “Urban Growth Centre” in the Province’s Growth Plan for the Greater Golden Horseshoe (2006). Other parts of the Town are also expected to continue experiencing rapid population growth. The current population of 95,879 is expected to grow to 161,750 by 2021 – an increase of nearly 200% above the 2006 population. While new residents will bring diversity and opportunities, this population growth will also increase demand for housing and place pressure on the Town’s grey infrastructure (e.g., roadways, water servicing) and green infrastructure (e.g., trees, parks and natural areas). These pressures, combined with other present and emerging threats such as pests and diseases, climate change, and competition for resources, will require long-term planning, active management, ongoing monitoring, and creative problem solving to sustain the urban forest as a healthy and growing part of the community. Estimates for the average lifespan of an urban tree vary widely, but most range from just 7 to 30 years. A number of factors can reduce tree longevity, including: • • • • • • • • •

Limited post-planting care and maintenance of young trees Pests, pathogens and diseases, which disproportionately affect stressed urban trees Competition by invasive species Inadequate soil volume and quality to sustain large, healthy trees Competition for above- and below-ground space with other municipal infrastructure Land use change and pressure from competing land uses Limited financial and human resources for urban forest monitoring and maintenance Lack of public awareness, engagement and support in urban forest stewardship activities Climate change and extreme weather events

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2. Responding to the Challenges: Strategic Urban Forest Management Planning Strategic urban forest management planning has been adopted by a number of municipalities across North America and beyond as a tool to address many of the same challenges experienced by Milton’s urban forest. The primary purpose of this Urban Forest Management Strategy is to identify the most effective ways to coordinate policies, practices and procedures pertaining to all tree-related activities undertaken by the Town of Milton and to improve the Town’s ability to manage the urban forest in a proactive manner. The recommended actions will support the longer-term goal of achieving urban forest sustainability and will lead to marked improvements in the health, longevity and function of the Town’s urban forest. However, it is important that proposed actions are based upon achievable targets and are proportionate and consistent with the Town’s size and available resources.

What is Urban Forest Sustainability? There are many definitions of sustainability, and sustainability can be measured in different ways (see Criteria and Indicators, page 10). A sustainable urban forest is one that maximizes and perpetually provides the numerous environmental, economic, and community (social) and health benefits of wellmanaged urban trees and shrubs.

While this plan is primarily intended for use by Town staff, it is also meant to be an accessible resource for all stakeholders and Milton’s residents. By pursuing the various strategies and best practices outlined within the plan, individuals and groups of all kinds will be able to work together towards improving and expanding Milton’s urban forest.

Ontario Municipalities with Urban Forest Management Plans A number of Ontario municipalities are realizing the benefits of strategic urban forest management planning. These include the Cities of Burlington, Guelph, Kingston, London, Mississauga, St. Catharines and Thunder Bay, and the Towns of Ajax and Oakville.

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2.1. Plan Structure and Implementation 2.1.1. Three-tier Structure

Although this strategy is focused on a 10-year planning horizon, active adaptive management will ensure that it carries on as a ‘living document’ well beyond that time frame. This is achieved, in part, through a multi-part planning framework that is divided into three tiers, as well as a built-in periodic review cycle. •

Tier 1: 10-year Strategy (2015-2024) (this document) o Sets the vision, goals and objectives to be achieved o Reviews current practices in Milton o Considers best practices from technical and scientific literature o Identifies opportunities for improvement of Milton’s urban forest management program



Tier 2: Five-year Management Plans (2015-2019 and 2020-2024) (to be developed) o Link between guiding principles and daily on-the-ground operations o Action-based, prioritized recommendations for improvement o To be developed by the Town of Milton based upon 10-year Strategy recommendations o To be implemented by various departments o To be reviewed at end of every 5th year of implementation by the Town’s urban forestry working group o Ensures active adaptive management is implemented



Tier 3: Annual Operating Plans (to be developed) o Guides day-to-day operations o Includes plans for planting, pruning, removals, inspections, inventory maintenance and public engagement/outreach o Prepared each year by Town’s urban forestry working group

Figure 2: Structure of the Town of Milton Urban Forest Management Strategy and implementation.

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2.1.2. Active Adaptive Management

Forested ecosystems are complex dynamic entities, particularly with the addition of a human element. Those involved in urban forest management cannot always predict the changes or events, such as severe weather, pest infestations or changes to resource allocation priorities that may impact the ability to achieve urban forest sustainability. For this reason, the concept of active adaptive management is firmly embedded in this urban forest management strategy. Adaptive management requires that a problem or issue be carefully assessed and understood before a strategy to solve it can be designed and implemented. The outcomes of the initial strategy are then monitored in a systematic manner, and any required adjustments are made based upon experience gained and any new information. The adjusted approach is implemented and the evaluation cycle continues for as long as is necessary to accomplish the desired goals or to accommodate changing environmental, social or policy directions. What is Active Adaptive Management? A systematic process for continually improving management policies and practices by learning from the outcomes of previously employed policies and practices. In active adaptive management, management is treated as a deliberate experiment for the purpose of learning. (United Nations Millennium Ecosystem Assessment, 2005)

2.1.3. Strategy Review and Monitoring

Various aspects of this strategy and the implementation of its recommended actions must be periodically reviewed and, if necessary, adapted to ensure ongoing progress. Mechanisms for review are built in to the strategy through the three-tiered framework and through the principle of active adaptive management. In keeping with these principles, the successes and shortcomings experienced during each five-year management planning period should be reviewed, and findings should be incorporated into the subsequent management plan. This review should be undertaken every five years by a Town urban forestry working group. The review process should include a review of the status, timing and anticipated budgetary requirements of each action of the strategic plan, as well as a review of the Criteria and Indicators-based monitoring framework.

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Measuring and Monitoring Sustainability: Criteria and Indicators Clark et al. (1997) developed a suite of criteria and indicators (C&I) to monitor performance of an urban forest and its management relative to an optimal sustainable state. Kenney, van Wassenaer and Satel (2011) refined this original framework to make it a tool for applied urban forest management planning and monitoring. The framework includes 25 different criteria, assessing the community’s status relative to indicators in the realms of the Community Framework, Resource Management Approach and Vegetation Resource. This C&I framework can be utilised to establish a baseline analysis at the outset of the urban forest management planning process, as well as during regular plan review stages, in order to assess progress towards achieving an optimal sustainable state.

2.1.4. Strategy Content

This Strategy addresses relevant issues under five topic areas, as follows: • • • • •

Understanding the Urban Forest, which reviews the existing tree inventory, considers strategies for improving the Town’s understanding of its urban forest resource, and explores opportunities to integrate trees into an effective asset management system; Caring for the Urban Forest, which reviews the implementation of urban forest health, maintenance and risk management in the Town; Growing the Urban Forest, which reviews tree establishment practices and programs; Planning the Urban Forest, which examines relevant legislation, policies and guidelines and explores how planning tools can promote urban forest sustainability, and; Supporting the Urban Forest, which focuses on opportunities for community and stakeholder engagement, stewardship and partnership.

For each of the five topic areas, the strategy considers: • • •

The Current Status of practices and policies implemented by the Town; Best Management Practices and Precedents from the technical and scientific literature, and from comparable municipalities within North America, and; Opportunities for Improvement of Milton’s urban forest management program, based on a ‘gap analysis’ considering current and best practices, and focusing on actions that are practical and costeffective.

Recommended action items are presented in Section 7. They have been developed based on careful consideration for identified opportunities for improvement under each topic area, and on extensive consultation with Town staff.

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3. Setting the Direction The vision, principles and strategic objectives for Milton’s Urban Forest Management Strategy provide a guiding framework that takes into account the local context and specific management issues faced by the Town. They have been developed with consideration for Milton’s biophysical and land use context, and in consultation with the Town’s Urban Forest Steering Committee. They also support the Town’s broader commitments to environmental sustainability by sharing common strategic and visioning elements with other Town plans.

3.1. Policy Support for this Strategy This Urban Forest Management Strategy is directly supported by the Town of Milton’s Strategic Plan, Destiny Milton 2 (2006), which states that one of the Town’s key goals is to provide: A thriving natural environment that is a valued community asset to be protected, maintained and enjoyed. A sustainable urban forest also relates to the Town’s objectives for well-planned spaces, a safe and healthy community, and a diverse and sustainable economy. In addition, one of the goals of the Town’s Environmental Control policies, as outlined in Milton’s Official Plan, is to: Maximize the retention and enhancement of [the] existing urban forest and to encourage new planting… (Sec. 2.3.2.2) The development and implementation of a strategic urban forest management plan is a key means to help ensure that these goals, and other targets for a sustainable and livable community, are met.

3.2. Vision The vision for Milton’s urban forest, to be realized through the implementation of this Urban Forest Management Strategy, is presented below: The Town of Milton values its urban forest for the environmental, economic, community and health benefits it provides to its community. The Town recognizes the value of this community asset in its planning and our day-to-day operations. This asset is sustained by the Town as it works towards proactive management and enhanced stewardship and partnerships in support of its urban forest.

3.3. Guiding Principles

The following principles have guided the development of this urban forest management strategy, and are also intended to guide its implementation.

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1. Develop a better understanding of the urban forest to support more effective management. 2. Plant the right tree in the right place with adequate soil volume and quality to reduce infrastructure conflict, the spread of invasive species, poor tree health and tree-related risk. 3. Implement more proactive tree management to achieve a healthier urban forest, a more livable community, and reduced urban forest management costs over time. 4. Recognize trees as essential municipal green infrastructure to ensure that they are planned for, maintained, and replaced as required. 5. Implement an active adaptive management approach to ensure that the Town is able to effectively respond to new challenges, implement new techniques, and benefit from developments in the field of urban forestry. 6. Engage the local community in stewardship and support of the urban forest to achieve the vision and objectives of this Strategy.

3.4. Strategic Objectives The Town of Milton seeks to achieve the following objectives though the implementation of this strategy over its 10-year planning horizon. 1. Allocate adequate human, financial and operational resources dedicated to urban forest maintenance, monitoring and planning; 2. Increase the proportion of proactive urban forest management and reduce the amount of reactive management needed; 3. Increase urban forest structural and species diversity, and increase the number of native, noninvasive tree species tolerant of urban forest stressors such as climate change, pests and diseases; 4. Acknowledge the importance of the urban forest in future high-level planning documents, and create and implement policies that support its protection and enhancement; 5. Expand the knowledge base about current conditions of the Town’s urban forest; 6. Increase awareness among Town residents, staff and representatives about the wide range of benefits provided by the urban forest, and about how to manage it to ensure its long-term sustainability, and; 7. Expand stewardship initiatives, increase community engagement, and develop more partnerships that support the urban forest.

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4. Current Status of Urban Forestry in the Town of Milton 4.1. Understanding the Urban Forest: Tree Inventory and Asset Management 4.1.1. Importance of a Tree Inventory and Asset Management System

Many municipalities maintain inventories of a wide variety of infrastructure elements, such as fleet vehicles or government facilities. Far fewer communities fully benefit from maintaining a similar knowledge of their green infrastructure components, including municipally-owned trees. Typically, a tree inventory identifies individual trees within a given study area and assesses a range of variables such as location, size, health and condition; more advanced inventories will also include maintenance requirements. A comprehensive tree inventory and asset management system which can track, prioritize and plan maintenance activities is one of the most useful urban forest management tools available. Key benefits of a tree inventory include: •

A better understanding of the urban forest: A tree inventory can include, among other attributes, tree species, size and age data. Combining this information with spatial data, urban forest managers can assess indicators of urban forest structural and species diversity and improve planning and implementation of tree establishment, tree maintenance and urban forest health monitoring.



Improved urban forest maintenance: A detailed tree inventory can enable urban forest managers to accomplish a variety of goals. For example, priority-based maintenance requirements can be planned in a proactive manner, species-based pest management strategies can be developed and implemented, and tree establishment needs, priorities and opportunities can be assessed.



A tool for public education and outreach: A tree inventory can act as a centrepiece for public education and communication efforts by highlighting individual significant trees, species diversity trends, and potential threats or challenges (such as Emerald Ash Borer).

4.1.2. Milton’s Existing Tree Inventory

In 2009, the Town undertook an inventory of municipally-owned street trees in eight of the Town’s longer-established neighbourhoods (collectively called Urban Milton in this Plan to distinguish from the Old Milton neighbourhood), bounded by Steeles Avenue, Bronte Street, Thompson Road and Derry Road2. This inventory collected identifying attributes, including species, size (diameter at breast height 2

Inventoried neighbourhoods include Bronte Meadows, Dorset Park, Fallingbrook, Forest Grove, Mountain View, Old Milton, Timberlea, and Valley View.

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in centimetres), overall condition (dead, poor, fair, good or excellent) and hazard potential (yes/no) for 8,880 street trees. In addition, the Town undertook a Town-wide survey to identify ash trees, due to the impending threat of the Emerald Ash Borer (Agrilus planinpennis) beetle, which feeds on this genus of tree and causes widespread mortality. The ash tree inventory found approximately 4,000 ash street trees in the Town. Combined with an inventory of trees in new subdivisions, it is estimated that the street tree population in Milton is approximately 18,729 trees. The Urban Milton inventory shows that relatively few tree species comprise a majority of the urban forest, in the older area of the Town. In Urban Milton, Norway maple (Acer platanoides) and green ash (Fraxinus pennsylvanica) account for nearly 40% of Town-owned street trees. The genus Acer (maple) alone makes up almost 40% of Urban Milton’s municipal trees, while Fraxinus (ash) makes up an additional 25%. Only 7 genera 3 make up 90% of all street trees in Urban Milton. This reliance on just a small selection of species is potentially problematic, especially considering the threat currently posed by the Emerald Ash Borer, which will likely eliminate all untreated ash trees throughout the Town within the next 10 years. The removal and replacement cost of ash trees may exceed $2.24 million by 2019, and the entire EAB management program is estimated to cost over $3 million by 2020. Urban Milton’s street tree population exhibits an ‘inverse-J’ DBH 4 curve (Figure 4), which means that the majority of the street tree population is made up of younger, smaller trees. This population dynamic suggests that, if maintained at optimal health and provided with adequate growing space, the street tree population will grow to continue to provide a wide range of urban forest benefits over time. However, there are many urban forest health challenges, as described throughout this document, which may prevent many of these young trees from reaching the larger size classes that are vital for the provision of urban forest benefits. As such, a key objective of the urban forest management program should be to care for these younger trees and enable them to grow to reach full maturity. The 2009 tree inventory and associated data management structure (a Geographic Information System database) fulfilled its intended purpose, which was to identify tree species (particularly ash trees). However, the future management utility of the existing inventory is relatively limited due to the level of detail of attributes collected. For example, while the inventory shows that approximately 1% of street trees in Urban Milton may pose elevated risk potential and that over half are in less than good condition, no tree-specific management recommendations are provided. The data may suggest that efforts to improve overall tree health, such as watering, mulching and pruning, may be required. The inventory also suggests that certain tree species are over-represented in Urban Milton, and future tree establishment efforts should consider underutilized and less common species. The tree inventory is not regularly kept up-to-date as trees are maintained, but is occasionally updated as trees are removed. Generally, the updating process is relatively informal, and the inventory does not inform the operations of the Town’s contracted tree service providers or the scheduling of maintenance operations.

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The 7 genera include Acer (maple), Fraxinus (ash), Gleditsia (honey locust), Pinus (pine), Tilia (linden), Picea (spruce) and Quercus (oak). Diameter at Breast Height (DBH) is a standard measurement of tree size, and is measured at 1.37 m above grade on the main stem (trunk) of the tree. 4

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Additional tree data are also added by the Community Services department to a separate inventory for trees planted in new developments, based on as-built drawings. This inventory database is separate from the 2009 street tree inventory, and has relatively little management utility at the current time beyond listing species, size, condition, date of planting and location, and for planning inspections. As an improved Level of Service for trees is implemented, this tree inventory may be used to plan young tree structural pruning or implementation of pruning cycles.

Figure 3: Example of data in 2009 Urban Milton street tree inventory.

Figure 4: Diameter at breast height (DBH, 1.37 m above grade) distribution of street trees in Urban Milton neighbourhoods, 2009. Note that the majority of trees are in smaller or mid-size classes. Town of Milton Urban Forestry Management Strategy

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Figure 5: Top ten tree species, eight ‘Urban Milton’ neighbourhoods (2009 street tree inventory).

Figure 6: Top seven tree genera (top 90%), eight ‘Urban Milton’ neighbourhoods (2009 street tree inventory).

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4.2. Caring for the Urban Forest: Tree Maintenance, Risk Management and Urban Forest Health Because trees in the urban forest are living things, they require a long-term commitment to management and care. Urban forest health and condition must be monitored and maintained in order to increase tree longevity, reduce tree-related risk and ensure that urban forest benefits continue to be provided to residents of the Town of Milton.

4.2.1. Urban Forest Program Administration

Currently, the Town of Milton does not operate a formalized urban forestry management program. No Town department has the direct responsibility to manage Town-owned urban forest resources, and responsibility for various aspects of urban forest management is generally shared between the departments of Community Services, Engineering Services and Planning and Development. The general urban forest-related responsibilities of each department are described below.

The Community Services Department: • • • • • • • •

Plans, designs and constructs Town-owned parks, and off-road trails within open spaces and natural areas Reviews and comments on all development applications as they relate to urban forestry on public lands (i.e., street trees, woodlot conveyance, naturalized channels and stormwater ponds, natural open space conveyed to the Town) Conducts inspections of plantings in new subdivisions to ensure compliance with approved landscape drawings and standards Maintains the existing tree inventory and acquires as-built information of subdivision plantings to incorporate into the existing inventory Manages tree establishment and replacement requests in unassumed subdivisions Manages the development and implementation of strategic urban forest initiatives Organizes and implements public education initiatives and community tree planting events Provides liaison function between developers and new residents in unassumed subdivisions

The Engineering Services Department: • • • • • •

Maintains park and open space lands (through Operations division) Administers urban forest maintenance (street tree pruning and removal) contracts Implements urban forest health maintenance and monitoring activities Manages tree establishment and replacement requests in assumed subdivisions and Regional roads following capital construction Plants new trees in capital roads projects Maintains municipal infrastructure (which may adversely affect or benefit existing and future trees)

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The Planning and Development department: • •

Establishes policies, regulations and standards guiding land use and development, which may affect the existing and future urban forest Reviews and imposes conditions on proposed development, which may include tree planting or protection

In 2011, the Town established the Urban Forestry Pilot Project, bringing together staff from several departments to begin working together to achieve several objectives under the Urban Forestry Steering Committee for a 1-year term. This project had five key objectives, which include: • • • • •

Improving coordination of urban forestry issues; Reviewing current approval practices and make recommendations to possible improvements in dealing with public inquiries; Developing an approved “Urban Forestry Strategy” for Council consideration (represented by this document); Developing a Level of Service for Town trees, and; Updating Council regarding tree disease issues (especially black knot fungus and Emerald Ash Borer).

Staff suggest that there is generally a good working relationship among staff from all departments in relation to urban forestry issues, but the key to long-term success is to implement improved processes that facilitate information sharing and communication and to coordinate various urban forest management activities.

4.2.2. Urban Tree Maintenance – Public Trees

Trees located within municipal rights-of-way or other public properties (parks, stormwater ponds, etc.) are the maintenance responsibility of the Town. In 2008, staff proposed a Level of Service (LOS) for street trees which included minimum intervals for inspection (5 years for old trees, 10 years for young trees, and annual in high profile areas), basic criteria for determining maintenance requirements such as removal, and other conditions. To date, this LOS has not implemented. Some of the provisions of the proposed LOS are adequate, such as the mulching, watering and stump grinding guidelines. However, some, such as the proposed lengthy inspection intervals, are inconsistent with an effective proactive management approach, as evidenced in current practices elsewhere. Instead of being maintained under the 2008 proposed Level of Service, municipally-owned trees are maintained on a largely reactive basis, whereby the Town’s tree maintenance contractors are on call to address tree health and risk issues as they arise. Through its contractors, the Town also maintains street trees along Regionally-owned road rights-of-way. Works on Regional roads are done by the Town or its contractors and billed back to the Region. The Town’s Community Services and Engineering Services Department customer service representatives receive resident street tree inquiries, such as calls for inspection, pruning, and new or replacement

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planting. Calls for tree management in established neighbourhoods or assumed subdivisions are transferred to Engineering Services and, if necessary, the Town’s privately hired tree maintenance contractors may be dispatched to address the service requests. If the subject trees are located in unassumed subdivisions, when trees are not yet the responsibility of the Town, staff advise callers that their queries will be forwarded to the developer’s landscape consultant for review and follow-up. This may include the assessment or replacement of the subject trees. The Town will ensure that any outstanding issues with regards to plant material are addressed prior to commencement of the Maintenance Period and Assumption of the subdivision.

4.2.3. Urban Tree Maintenance – Mature Trees

Since 2009, a small subset of Town-owned mature trees located in Kinsmen, Melanie, Dempsey and Wallbrook parks have been maintained by a local tree service provider at no cost to the Town under the Mature Tree Adoption Program. Maintenance has focused on soil quality improvement, and has included mulching, watering, mycorrhizae (beneficial fungus) application and soil decompaction, in addition to maintenance pruning. Since its inception in 2009, the program has been generally successful in restoring the health of the maintained trees, at no cost to the Town. Staff report that this program, which is administered by the Community Services Department, is effective and that the Town will continue operating the program in its current format. The program is described in detail in staff report COMS-050-07.

4.2.4. Urban Tree Maintenance –Newly Planted Trees

Under the terms of subdivision agreements, maintenance of newly-planted trees in unassumed subdivisions is the responsibility of the developer until the subdivision is assumed by the Town. Prior to Assumption, street tree plantings, stormwater management plantings, woodlots, channel plantings and natural or naturalized area plantings are inspected by Community Services staff for compliance with approved drawings. Any outstanding deficiencies are rectified prior to the start of the Maintenance Period and Assumption. Following Assumption, maintenance responsibility is transferred to the Town and trees are maintained on a largely reactive or as-needed basis. Homeowners in new residential developments are informed about the importance of watering and mulching newly-planted trees through an informational door hanger, and are encouraged to provide basic care for young trees. Door hangers (see Section 4.5) are development approval requirements and are provided by the developer. Trees planted by the Town as part of capital parks and open space projects or infill planting are provided with a two-year warranty by the landscape contractor. There is no requirement that the contractor actively maintain the tree during this period, provided that it is transferred to the Town in good health and condition in accordance with contract specifications.

4.2.5. Urban Tree Maintenance - Tree Risk Management

Trees in urban areas may pose risk to persons or property, particularly if tree maintenance is undertaken on a reactive rather than proactive basis. The potential for tree-related risk increases as trees age, if tree health and condition decline, and if young trees are not properly pruned to develop good structure.

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Currently, the Town of Milton does not implement a formalized or proactive approach to tree risk assessment, management and mitigation. Risk associated with publicly-owned trees is addressed on a complaint basis or when issues are observed by staff. When such issues arise, the Town’s tree maintenance contractor is dispatched to conduct the required mitigation activities, which are typically limited to corrective pruning or tree removal. The Town does not regularly cable, brace or actively inspect trees which may pose an elevated level of risk. Risk mitigation is generally attempted through corrective pruning or removal, although some trees have been cabled in the past. Tree risk is expected to be addressed in all Woodlot Management Strategies, which are a required component of development applications when woodlots are present. The developer is expected to mitigate identified tree risk prior to Assumption of the woodlot by the Town, but subsequent risk management by the Town post-Assumption is conducted on a reactive basis. It should be noted that currently there is no Town “Terms of Reference” to guide the development of Woodlot Management Strategies.

4.2.6. Urban Forest Health Management - Overview

The concept of urban forest health management suggests that overall tree condition (e.g., structure, stability, etc.) and tree health (e.g., foliage vitality, growth rates, etc.) must be actively monitored and maintained to ensure that: • • • •

tree longevity is promoted to the greatest extent possible, which reduces removal and replacement costs, increases urban forest connectivity and canopy cover, and confers more urban forest benefits trees are able to attain the greatest possible size, which increases leaf area and enables the urban forest to confer a greater amount of benefits tree risk is reduced as trees are more structurally sound, and tree pests and diseases are prevented from causing widespread damage to the urban forest.

A less healthy urban forest is more costly to maintain, as trees must be pruned, removed and replaced more frequently, and tree related risk may increase. Reduced tree health may also result in fewer urban forest benefits being conferred to Town residents, as leaf area and canopy cover are reduced. A number of stressors may adversely affect urban forest health. While many, such as pests and diseases, are naturally-occurring, others are human caused. Furthermore, human-caused stressors may increase urban forest susceptibility to naturally-occurring stressors and reduce urban forest health. Milton manages urban forest health on both a proactive and reactive basis. Proactive urban forest health management focuses on ensuring that trees are provided with the requisite conditions so that health and condition do not deteriorate over time. Reactive management responds to and attempts to mitigate stressors so that tree health and condition are preserved or improved. Table 1, below, outlines Milton’s urban forest health management activities.

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Table 1: Summary of Milton’s urban forest health management activities (proactive and reactive). Proactive UF Management Activities •

• •

• • • •

Engineering and Parks Standards, 2014 tree species and stock selection standards, soil quality guidelines 1 to 2-year warranty period for newly-planted trees Mature tree adoption program (provides some mature trees with site improvements such as mulch and mycorrhizae) Ash tree inventory and Emerald Ash Borer (EAB) Strategy (combination of proactive and reactive) Street tree inventory (Urban Milton) and limited new community tree inventory from as-builts Woodlot management strategies for new woodlots incl. tree risk mitigation Public education door hangers re: young tree care and targeted UF management activities (e.g., black knot Prunus removal)

Reactive UF Management Activities •

Most street and park tree maintenance operations (i.e., pruning and removal)

• •

Request-based street tree planting/ replacement Enforcement of By-law 115-2005 (Road Fouling) to reduce stressors upon boulevard trees

4.2.7. Urban Forest Health Management – Pest and Disease Management (General)

The effective management of pests and pathogens is vital to maintaining a healthy urban forest. Urban forest pests primarily include insects which feed on trees, while pathogens are diseases (primarily fungal) which may affect individual trees or entire populations. In general, the Town does not actively manage most pest and pathogen issues. Trees infested with decay pathogens are pruned or removed, as required, and insect pest infestations (with the exception of Emerald Ash Borer) have not been significant enough to warrant intervention. Town Policy No. 13 (2005) aims to “minimize the use of pesticides by the Engineering Services Department”, and states that “the use of pesticides for the control of insects and disease in trees … will occur only when there is no other reasonable alternative and the life of the tree/plant is at stake.” In 2011, the Town undertook a three-year process of replacement and removal of Schubert chokecherry (Prunus virginiana) trees affected by black knot fungus disease. This disease causes unsightly growths which can ultimately lead to tree mortality. Town staff identified some 400 affected trees in need of removal and replacement, and informed community residents about the reason for these removals. The black knot management program is described in detail in staff report ENG-020-11.

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4.2.8. Urban Forest Health Management – Emerald Ash Borer

In 2009 staff tabled report ENG-009-09 to inform Council about the impending threat posed by Emerald Ash Borer (EAB) to all ash trees in the Town of Milton, and beyond. Emerald Ash Borer (Agrilus planipennis) is a non-native invasive wood-boring insect which has continued to cause widespread mortality to ash (genus Fraxinus) trees across eastern North America since its discovery in 2002 in the Windsor and Detroit area. EAB infestation poses one of the most pressing challenges to Milton’s urban forest, as it will require significant financial and human resources in the coming years to protect, remove and replace affected trees. The potential impact has been somewhat reduced due to the Town’s ash tree planting moratorium, imposed in 2007. The 2009 staff report also recommended that an inventory of Town-owned ash trees in parks and boulevards be undertaken. Conducted in 2009, the inventory found 3,940 Town-owned ash street trees. In 2011, staff estimated a cost of upwards of $4 million over 15 years to address tree removal and replacement due to EAB (as outlined in report ENG-020-11). In 2013, the Town commissioned a visual assessment of all inventoried ash trees. Approximately 2,500 trees were found to show possible signs or symptoms of EAB infestation. In report ENG-028-13, the Town outlined its 7-year, $3-million EAB management strategy, which includes protective treatment of significant ash trees (in good to excellent condition and greater than 20 cm DBH) and removal and replacement of infested or dead ash trees. The strategy combines proactive and reactive approaches, as trees are proactively treated but removal and replacement is currently guided by estimated ash tree mortality rates. Information about the EAB management strategy has also been posted to the Town’s website.

4.2.9. Urban Forest Health Management – Trees in New Developments

Street tree planting is required as a condition of all new subdivision development in the Town of Milton, and has been for a number of years (see Growing the Urban Forest section of this plan for more detail). The Town’s 2014 Engineering and Parks Standards manual (Sec. 1.4.27.16) requires that the Developer “must maintain all plants in a vigorous and healthy growing condition”, which includes activities such as weeding, watering, pruning, and pest and disease control. However, the Town does not actively inspect trees prior to Maintenance Period and/or a security reduction request by the developer’s landscape architect to confirm that such maintenance is undertaken, and trees that appear to be in good condition are generally accepted just prior to the Maintenance Period of the subdivision. Some developers operating within the Town do actively implement such maintenance, while others do not, which potentially leads to increased rates of young tree mortality, even following subdivision Assumption. Following Assumption by the Town, young trees in new developments are maintained on a requestbased or reactive basis, in the same manner as other Town-owned trees.

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4.2.10. Urban Forest Health Management – Tree Protection

The protection of trees during site development and construction activities is generally understood to be more effective in maintaining the sustained provision of urban forest benefits than planting new trees, and is also typically less costly. Construction and development activities can adversely affect existing trees, and trees on private and public property are equally vulnerable. Virtually all parts of a tree can be impacted by construction, including roots (through cutting and soil compaction), trunks (physical damage such as abrasion), branches (fractures or poor pruning) and foliage (chemicals or exhaust heat). Such damage can lead to decay, structural and stability issues, canopy decline and eventual mortality, and construction-related damage may not become evident until several years after a project is completed. In some situations, tree preservation on development sites may not be feasible. Where protection is possible, however, the implementation of strategies to inventory, protect and monitor trees before they can be adversely affected by construction activities is critical to sustaining the urban forest. Currently, Site Plans and Subdivision Plans are reviewed by a multi-departmental team to ensure compliance with Town development and engineering guidelines and standards. Potential impacts upon existing and or future Town-owned trees are reviewed by staff in Parks Planning, Community Services (Manager, Coordinator, Parks Planner). Applicable technical studies such as subwatershed, stormwater impact, functional servicing and natural heritage as approved by other Town departments and/or public agencies, inform this review. Conditions may be imposed upon development plans to provide for protection of Town-owned tree assets, but private tree protection is not generally considered as part of development plan review. The Town of Milton does not have a specific tree protection policy for trees potentially affected during construction, including Town-owned trees, although staff are usually successful in ensuring protection of public tree assets through the application of fencing details and setbacks as well as securing compensation for their damage or removal. Protection of woodlots and natural areas is also usually considered during development plan review. Despite the lack of a specific Town-owned tree protection policy, several sections of the Town’s 2014 Engineering and Parks Standards Manual do provide for the protection of existing Town-owned trees, and could enable the Town to impose more effective conditions upon development applications to ensure that Town-owned trees are adequately protected. These sections are highlighted in Table 2, below. By-law No. 33-2004 “A by-law to protect and conserve topsoil and for prohibiting or regulating the alteration of property within the Town of Milton and to repeal by-law no. 23-96” also enables the Town to withhold Site Alteration or Topsoil Removal permits if the proposed works will result in “a detrimental effect on any Vegetation that has been designated for preservation; or an undue detrimental effect on the natural environment of the area”.

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Table 2: Tree protection guidelines in Town of Milton 2014 Parks and Engineering Standards Manual. Section 1.1.14.2 ‘Design’

1.1.21.1 ‘Criteria’

1.1.21.3 ‘Guarantee and Inspection of Street Trees’ 1.4.1.5 ‘Site Works’ 1.4.11.1 ‘Site Examinations’ 1.4.11.3 ‘Tree and Shrub Protection’

Guidelines Construction Fencing is required as follows: a) Tree protection fencing • Fencing to be 1.2 metre high page wire fencing complete with caution signs to be placed 1.0m beyond at the drip line of the trees to be protected. Ref Std. Dwg. P-1 • In some situations the Town may require tree protection hoarding due to sensitive nature of the existing vegetation to be protected during construction. Ref Std P-2 a) Protection of Existing Street Trees • Existing street trees located within a public right-of-way may not be removed or damaged in any way. Developers shall make every effort to protect existing street trees and maintain the optimum growing conditions during construction. Where development or re-development of a site impacts existing street trees, the Town may undertake remedial measures, including the removal of the street tree, if so required. All costs will be borne by the Developer. In addition, the Developer shall be required to replace the damaged or removed street trees with an equivalent total diameter at breast height (DBH) or, at the discretion of the Town, provide an equivalent value in funding to the Town for street tree planting. • Bare soil or homeowner built structures around street trees within the road allowance will not be accepted and will be removed by the developer’s forces prior to Assumption of the subdivision. a) Tree protection • All mature trees and woodlot edges are to be protected as per Town standards. (Refer to 1.1.14.2) e) Protection • Protect existing vegetation as directed on site by Landscape Architect prior to commencing any site works. Refer to Std. Dwg. No. P-1. Protection should be in accordance with an approved Site Alteration Permit, if applicable. a) General • The Contractor shall be required to protect the root systems and habitat of existing trees from damage due to excavation, compaction or contamination resulting from construction. For the installation of conduits, the Contractor may be required to bore/tunnel under the tree’s root system using methods and equipment acceptable to the Town. The Contractor shall also supply equipment that maintains existing tree canopy when working under overhanging limbs. No trees shall be pruned without prior approval from the Town. c) Materials • Protective barrier to consist of rigid page wire fencing complete with iron "T" bars placed at 2.5 metres o.c. (maximum spacing). Fencing is to be 1.2m high. Refer to Std. Dwg. No. P-1. d) Installation • Prior to the start of any site work, the Contractor shall supply and install tree protection barriers around each tree and shrub grouping designated on the site plan to be protected, or as directed by the Town. Protective barrier, as a minimum, is to be located at the outer limit of the drip line of the tree. The drip line is defined as the outside edge of the tree canopy. Protective barriers

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Section

1.4.18.4‘Woodland Mulch Trail’ 2.1.14 ‘Subdivision Grading Plans’

Standard Parks Drawings P-1 ‘ Tree Protection Fencing’ and P-2 ‘Tree Protection Hoarding’

Guidelines for shrub massings are to be located 1m minimum from the outside edge of the plants. No fill, machinery, or materials are to be placed within the protective barrier. No re-grading, including filling or excavation, is to take place within the protected area. All underbrush that is to be removed from within the protective barriers must be cleared by hand. The method of removal of brush from the protected area is to be approved by the Town. Contractor is responsible to remove tree and shrub protection upon final acceptance. e) Workmanship • The Contractor will be required to replace with material of equal value, at no extra cost to the contract, all plant material damaged as a result of improper installation or maintenance of protective barriers. f) Guarantee • The Contractor is responsible to ensure that the protective barrier is installed prior to the start of construction and is maintained intact until final acceptance of the project. a) Initial Layout • Path layout should not interfere with the root zone of trees with a DBH greater than 10 cm. The plans are to include the following information: 2.1.14.1 Existing Elevations at: e) regular intervals within any woodlot or other natural blocks where deemed necessary to determine the effect of grade change on tree preservation. 2.1.14.3 Other Required Information e) indicate existing trees and proposed tree saving limits. Indicate provisions for the preservation of any existing trees where identified for retention. Provide details for construction of tree protection fencing and solid hoarding, incl. dimensions, materials and installation notes.

4.3. Growing the Urban Forest: Tree Establishment Unlike forests in natural settings, the urban forest relies on direct human involvement to ensure it is sustained and expanded. Seeding or vegetative growth account for only a very small proportion of tree regeneration in Milton’s urban forest; most trees are planted by the Town, developers or private property owners. Growing the urban forest is critical to sustaining and replenishing leaf area and canopy cover lost through tree mortality and removal for residential, commercial or infrastructure development. The challenges of ensuring that the urban forest is sustained and expanded can be overcome by creating adequate space for trees through innovative site design, identifying areas in need of increased tree establishment, and applying new techniques and technologies to provide optimal growing conditions in otherwise stressful environments. Tree establishment decisions must also consider species diversity and distribution, stocking targets, development needs and budgetary constraints. Town of Milton Urban Forestry Management Strategy

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The implementation of a range of sustainable practices will ensure that existing and newly-planted trees contribute to urban canopy cover. Knowledge the varying requirements for different tree species, risk management, and greater use of a diversity of native tree species where appropriate to improve the overall resilience of the urban forest, are also key considerations.

4.3.1. Tree Establishment –Development The Town requires the establishment of street trees along public rights-of-way for all developments and redevelopments. The long-term objective of these plantings is to provide canopy cover and leaf area for new communities and ensure that urban forest benefits are provided to residents across the Town. Process In general, street trees in new developments are installed by the developer and at the developer’s expense. Tree planting plans must be submitted for Town review and approval. For subdivision development, trees must be planted by the developer at least one year prior to the beginning of the Maintenance Period, which itself typically lasts for one year or longer. This generally ensures that, at the time of Assumption, trees are in good growing condition as defined in the Town’s 2014 Engineering and Parks Standards Manual. For other types of developments, the developer is required to provide a 2-year guarantee for all required landscape plantings, including trees. The Town of Milton typically secures a letter of credit to ensure that the approved plantings are provided and are in acceptable condition upon Assumption of the plant materials. The detailed tree establishment process is described in Section 1.1.21 ‘Street Trees’ of the 2014 Engineering and Parks Standards Manual. Density and Spacing Unless there are conflicts with other infrastructure (driveways, utilities, signage, etc.), all residential frontages are required to be planted with at least one street tree, or with typical spacing of 9-12 m between trees. Flankages (e.g., corner lots) require two trees per flankage. Spacing is closer in industrial areas, and double rows of trees may be required. Ultimately, tree locations and spacing requirements may vary, and are reviewed by Town staff on a site-by-site basis. Stock Selection The Town’s stock selection standards for street tree planting consider requirements for species, size, and stock type. The 2014 Engineering and Parks Standards Manual includes a series of tables intended to guide tree species selection, which include lists of non-native and invasive plants, native plants, recommended street trees, and salt tolerant trees. 24 species/genera are included on the list of recommended street trees. Ash (genus Fraxinus) has not been approved for planting in Milton for a number of years, and is not considered an acceptable species due to its susceptibility to Emerald Ash Borer.

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Standards and Specifications Through the 2014 Engineering and Parks Standards Manual, the Town maintains a comprehensive series of specifications for plant stock, planting mixes, installation and maintenance. Although developers are expected to conform to these standards and specifications, compliance inspection is only undertaken at letter of credit reduction requested inspection, Maintenance Period inspections and inspections conducted prior to Assumption. Therefore, practices such as installation of inadequate stock, poor planting or inadequate maintenance may occur throughout the construction process, which may lead to increased rates of tree mortality and increased long-term maintenance requirements and costs.

4.3.2. Tree Establishment – Infill, Replacement and Capital Projects In addition to tree establishment in new developments and municipal parks, trees are also planted in Milton to fill available planting spaces, replace removed trees, and as part of municipal or Halton Region capital projects such as road works (either to replace removed or damaged trees, or as part of a streetscape design). This type of planting is conducted on an as-needed basis; the number of trees planted in a given year will depend upon the number of trees removed or upon the scope of capital projects (e.g., park redevelopment, road reconstruction, etc.) being undertaken. Standard planting specifications and details for the replacement tree planting program are the same as in the 2014 Engineering and Parks Standards Manual, helping to ensure that trees are planted in a consistent manner across the Town. As with street tree planting in new developments, compliance inspection to ensure quality of tree planting stock and implementation is limited to post-planting inspection. Halton Region projects such as road reconstruction or widening are generally expected to conform to Town standards for tree protection and tree establishment. However, Regional right-of-way plantings are not currently reviewed by qualified Town staff to ensure conformance, which may lead to missed opportunities for tree protection or tree establishment practices which may not conform to Town standards or expectations. This may result in future management challenges associated with trees planted on Regional roads (e.g., inappropriate species selection, inadequate establishment practices, inadequate soil quality or volume, etc.). Town and Regional standards and practices should therefore be reviewed for opportunities to coordinate standards and identify differences with the intent to improve tree protection, establishment and long-term survival on Regional projects. This review should be undertaken as part of the update of the 2014 Engineering and Parks Standards manual, development of a Town-owned tree protection policy, and implementation of an improved young tree establishment program, as recommended in this Strategy.

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4.4. Planning for the Urban Forest: Policies, By-laws and Guidelines 4.4.1. Town of Milton – Town-wide Strategies and Plans Strategic Plan (2006) Destiny Milton 2: Shaping Our Future (2006), the Town’s Strategic Plan, does not specifically use the words “urban forest” or “green infrastructure”, but clearly asserts the importance of green spaces and natural areas to the community, and provides specific direction to: • • • • •

consider the natural environment in decision-making, maintain, restore and enhance natural heritage where possible, integrate woodlots and other natural heritage features into the urban matrix, promote access to natural areas with trails while still protecting them from negative impacts, and educate the public on the benefits provided by natural heritage.

Destiny Milton 2: Shaping Our Future (2006) Vision: “Engaging, Balanced, Connected” Goals include: “A thriving natural environment that is a valued community asset to be protected, maintained and enjoyed”. Direction includes: “Maintain, restore and where possible enhance or improve the diversity and connectivity of natural heritage features and functions” “Protect, maintain and enhance woodlots in the urban area” “Educate the public on the benefits of the natural environment and the positive contribution the natural environment has on the Town”

Official Plan (2010) The Town of Milton currently has an updated Official Plan (through Official Plan Amendment (OPA 31) which was adopted by Council June 14th, 2010 and is currently awaiting Regional approval. Even though OPA 31 has not yet been approved (because the Region’s OPA remains under appeal), the Town’s policies related to trees and forests have not changed substantially with OPA 31 (with the exception of the definition for Significant Woodlands) and therefore the most current policies are cited below. In addition to a series of policies intended to identify, preserve and enhance natural areas and ecosystems as a whole, the Town of Milton’s Official Plan has a specific section dedicated to “Forestry”. The Town’s Natural Heritage System 5 includes many wooded features including significant woodlands,

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Carolinian Canada sites, and Halton Agreement Forests. In general, uses that will have a negative impact on the various Natural Heritage System features, or their functions, are not permitted. The strategic Forestry policies (policies 2.3.3) generally support the conservation, management and expansion of forested areas throughout the Town, including both forested areas and individual trees in the Urban Area and Hamlets. The Official Plan includes a fairly comprehensive set of strategic policies under its Forestry section that include commitments to: • • • • • • • • • •

develop a plan for maintaining an inventory of trees on public lands; establish annual targets and a budget for tree planting; replace all trees removed from road rights-of-way; ensure tree maintenance work related to utilities considers proper tree structure and new utility installation considers maximizing opportunities for trees and other vegetation; support a tree by-law that regulates tree cutting and removal in significant woodlots, Environmentally Sensitive Areas (ESAs) and natural heritage features; encourage the identification and designation of heritage trees; actively promote the Town’s forestry policies; collaborate with other public agencies including the Region, conservation authorities and Ministry of Natural Resources to promote reforestation and good forestry management practices; encourage public education and stewardship, and working with landowners in the Urban Area and Hamlets to support tree planting; and require a tree inventory, tree saving and tree planting plan for all developments.

The Official Plan also supports the Town’s forest and treed assets through: • •







the planting of a diversity of tree species (and other shrubs and herbaceous plants) as well as drought tolerant species as part of broader environmental policies (policies 2.2.2.13 and 2.3.2.12); tree planting in medians of wider roads (i.e. four lanes or more) (policy 2.8.3.25), enhanced tree plantings along major access roads (i.e., Regional Road 25, Steeles Ave., No. 5 Sideroad and James Snow Parkway) (policy C.8.2.2(c)), and enhanced streetscape design (including street trees) along other primary roads (policy C.8.2.2(g)); protection, enhancement and replacement of trees (and other vegetation) by prioritizing retention of naturalized areas, requiring replacement of significant trees / vegetation removed, and requiring integration of trees and other landscaping in all new developments (policy 2.8.3.50 a, b and c); landscaping requirements for new developments that ensure trees (and other landscaping) is predominantly comprised of native species, tolerant to urban stressors and the site conditions, and consider its ability to provide shade, screening (visual as well as for wind, sound and snow), and slope stabilization (policy 2.8.3.50 d); and retention of landmark trees and hedge rows where possible (policy 2.10.3.24).

The most substantive change to the Official Plan with OPA 31 is the adoption of the Region’s definition for a Significant Woodland, which is criteria-based and more specific than the former definition adopted from the Provincial Policy Statement.

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In addition, the Official Plan addresses canopy cover in the Central Business District (CBD). The policies recognize the importance of mature tree canopy and treed streets in the Town’s CBD, estimate the canopy cover in the developed portions of the CBD to be about 14%, and set a target for new developments to achieve at least 15% canopy cover within five years of issuance of a building permit. Milton Intensification Strategy (2010) The intensification strategy addresses the challenges of integrating trees, especially larger stature trees, in a built up environment, as well as the high value placed on having these assets in a downtown.

Town of Milton Intensification Strategy (2010) A successful street tree program results when the program is implemented with adequate resources and using a thorough understanding of urban forestry principles.

4.4.2. By-laws and Related Legislation Heritage Tree Legislation The Official Plan (2010) speaks to “encouraging the identification and designation of appropriate individual trees and tree stands as Heritage Features where appropriate” (policy 2.3.3.1(d)), although heritage trees are not specifically identified or defined in any Town document. The Ontario Heritage Act is one tool that can be used to designate trees on cultural heritage properties or landscapes if the trees are considered a heritage attribute. The Town’s updated Official Plan provides more explicit links to the requirements of the Act, requires consideration of cultural heritage through the development process, and also allows for the identification and designation of Heritage Conservation Districts, which can also require special consideration for proposed changes to trees within them. Tree By-laws The Region has a comprehensive by-law that regulates woodlands in the Town (as described below). The Town of Milton does not have any specific by-laws that regulate individual or small groups of trees on public or private lands. However, the Town does have several other by-laws that are used to help regulate activities that can negatively impact trees in the Town. By-law applying to Private Lands •

The Site Alteration By-law (033-2004) regulates and requires permits for the removal of topsoil and the placement of fill, as well as for any changes in grade. Permit applications must include the location of all trees with 10 cm dbh or greater, including their drip line, as well as the composite dripline of other vegetation, and approval may be required for some or all of the identified trees. This by-law applies to private lands.

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• • •

The Road and Curb Cuts By-law (075-2004) subjects removal of trees or shrubs to Halton’s Tree By-law, and requires Town approval prior to interfering, cutting or trimming any tree (including roots) in the right-of-way. The Property Standards By-law (141-2001) requires landowners to remove trees that are dead or damaged / decayed to the point where they present a hazard. The Road Fouling By-law (115-2005) provides some indirect protection to public trees by prohibiting unauthorised landscaping in proximity to trees.

By-laws applying to Public Lands • •

The Parks By-law (072-2006) prohibits the disposal of soil, plant trimmings or any other garbage (which if dumped within or around a tree’s dripline could result in damage). The Littering By-law (50-91) has been used to prevent and prosecute encroachments into Townowned woodlands such as dumping of yard or other waste, erection of structures, and removal of vegetation.

Town Zoning By-law The Town of Milton’s Zoning By-law (144-2003, June 2009 consolidation) has several requirements in it that support the protection and/or replenishment of the urban forest with respect to significant woodlands or other treed areas found within the broader Natural Heritage (formerly the Greenlands) System. For example, the zoning by-law: • • •

requires proposed accessory buildings and structures as well as other permitted uses (such as detached dwellings and forestry uses) in the Natural Heritage System (formerly called Greenlands) to be subject to the Regional Tree By-law; requires setbacks of at least 7.5 m from most land uses; and restricts the dimensions of these structures. It also allows for a holding provision to be placed on Draft Approved Plans of Subdivision until any obligations related to a Tree compensation Agreement between the owner and the Town have been met.

Species at Risk Legislation The provincial Endangered Species Act (2007) is another piece of legislation which regulates activities related to some species of trees that occur in Milton. The Act is administered and enforced by the Ontario Ministry of Natural Resources (OMNR) and applies to species listed as Endangered or Threatened in the Act. Listed species known to occur in Milton include Butternut, which is relatively widespread but endangered because of its susceptibility to a fungal pathogen, as well as a number of Carolinian species (e.g., Red mulberry, American chestnut).

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4.4.3. Town Guidelines and Standards Boyne Urban Design Guidelines (2010) The Official Plan provides some high level guidance with respect to trees and urban design. The Boyne Urban Design Guidelines (2010) provide current and detailed guidance in the Town of Milton. Although the document’s vision does not speak specifically to the urban forest, a “green” foundation is identified as a cornerstone of the community framework. This “green” foundation includes: tree-lined and pedestrian/bicycle supportive streets, integration of natural heritage, a connected and diverse system of parks and open space, and naturalized storm water management facilities. Town of Milton Engineering and Parks Standards (Revised 2014) The site-specific policies and standards are already covered under Section 4.3 (Tree Establishment), but it is notable that throughout the document there are a number of references to the installation of medium to large shade trees where possible (e.g., street tree species selection) as well as specific guidelines related to shade and general guidance for shade trees to be planted near seating areas along walkways and trails, as well as near play areas and in parks. Currently, when a Significant Woodland is identified through the development planning process by the Region, the Town may request conveyance of this woodland/woodlot and may integrate it in to the urban fabric. Wherever possible, these woodlands/woodlots have parks and/or open space located immediately adjacent to them. This can minimize impacts from adjacent residential homes, provide some supportive ecological functions to the woodland/woodlot, and ensure that the natural area is accessible to surrounding residents. As part of woodland conveyance to the Town, developers have been required by the Town to undertake tree risk management (e.g., edge hazard tree removal) and even invasive species control. Development of edge and interior trails and interpretive signage has also been undertaken by developers. Woodland Management Plans are typically required from developers as part of the woodland conveyance process, although there is no standard list of requirements to consider as part of these Management Plans, and therefore their level of detail and contents vary. The woodlot management plans are available for use by Operations, but ongoing maintenance of these features is not typically implemented due to staffing constraints and other maintenance priorities.

4.4.4. Halton Region Halton Region’s tree-related policies and by-laws are discussed in terms of their specific relevance to Milton’s urban forest below Halton Region Official Plan Halton has recently updated its Official Plan policies through Regional Official Plan Amendment (ROPA) 38. As with Milton’s Official Plan update, a number of the changes have been made to bring the regional plan into conformity with new provincial plans that have been updated or passed (i.e., Growth Plan for the Greater Golden Horseshoe, Greenbelt Plan, updated Niagara Escarpment Plan, and Parkway Belt

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West Plan). ROPA 38 was passed by regional Council in December 2009 but has been amended subsequently based on comments from the lower tier municipalities and the Province. It remains under appeal, and has not been finalized. ROPA 38 focuses on policies related to woodlands rather than individual trees. Under ROPA 38, Significant Woodlands 6 are considered Key Features within the regional Natural Heritage System (NHS), and under the current policies are protected from development or site alteration, requiring 30 m Vegetative Protection Zones within the Greenbelt and site-specific buffers within the NHS but outside the Greenbelt. Town staff have indicated that it is standard practice for the Region to identify significant woodlands in the Town, and for the Town to assume these woodlands through the planning process. This has resulted in 21 woodlots of varying sizes being assumed by the Town in the urban area. These woodlands are, for the most part, located immediately adjacent to Town parks and Open Spaces. The total area of urban woodlots in Milton is approximately 59 hectares. Typical to the recent Secondary Plan expansion areas, woodlots have been conveyed separately from the provision of parkland dedication and at no cost to the Town. Halton Region Tree By-law The regional tree by-law (121-05) regulates all woodlands of at least 1 ha, as well as between 0.5 and 1 ha where the lower tier municipality has so delegated their authority, as is the case in Milton. Generally, the by-law requires a permit for the injury or destruction of one or more trees within a regulated woodland, unless the trees are: hazardous; removed as part of normal farm practices or for personal use (up to a set limit); removed for activities that fall under one of the standard exemptions; or removed in accordance with an approved Forest Management Plan. Permits may be granted for harvesting in an Urban Area, or for other purposes through a “Special Council Permit”. This means that for any activities within a woodland of 0.5 ha or more on private lands in the Town, particularly within the Urban Area, the Region must be consulted. Conservation Halton In addition to regulating wetlands, hazard lands and shorelines, Conservation Halton has Guidelines for Stormwater Management Pond and Creek Realignment Planting Plans and Tree Preservation Plans (2005), which are currently under review. These guidelines: • • •

contain policies regarding the preservation and enhancement of vegetation in natural heritage systems within its jurisdiction; specify planting design techniques, appropriate native species, provide planting guidelines regarding topsoil, stabilization, monitoring, maintenance and species criteria, and preferred densities.

6

Significant Woodlands are identified as woodlands of more than 0.5 ha that meet one or more of the four established criteria.

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Development applicants may be required to prepare a tree preservation plan (to ensure there is no impact to existing trees within a conservation authority regulated area) during the development process, and in some cases, a re-vegetation / landscape plan may also be required. Conservation Halton requires that vegetation proposed within or near natural features be native to the Region, and applies a net gain principle when providing comments on re-vegetation / rehabilitation plans. They also comment on land-use planning applications submitted to the Region and lower tier municipalities under the Planning Act, including proposals where woodlands are involved.

4.5. Supporting the Urban Forest: Education, Outreach and Stewardship The Town of Milton currently has a number of educational and outreach tools that it has developed that are primarily focussed on the planting and care of trees in the municipality. These include information posted on the website, the door hanger program, and several outreach programs that support tree planting on public and private lands in the municipality. Conservation Halton’s mandate encompasses protection of the natural environment in general, including forested areas, and they have a number of outreach and stewardship programs that are available to residents of the Town. Halton Region also has a number of educational and outreach tools focused on forested areas in both the Region’s urban and rural areas.

4.5.1. Town of Milton The Town of Milton has developed various outreach materials related to trees, largely in response to the questions and concerns of its residents. These include door hangers, information sheets, educational signs, and tree and woodland care tips on the Town’s website. Since 2006, door hangers (Figure 7) have been used wherever new trees are planted in boulevards. These include information on how to care for newly planted boulevard trees, who to contact for more information, and on the benefits of trees. A similar approach has been used more recently to provide notice about the removal of chokecherry street trees (due to susceptibility to Black knot disease) and ash tree removals and treatment (due to Emerald Ash Borer) and to identify replacements with a diversity of alternate tree species. The Town has developed a basic information sheet (available on its website) of tree care tips and about woodlots and their functions in Town, and has created signs for specific projects that explain replanting activities (i.e., Mill Pond Trail Restoration Planting sign, McDuffe Park sign). The Town’s website includes pages on “Trees and Woodlots” and “Care and Maintenance of Street Trees” that provide specific guidance on individual tree care and care of woodlots, as well as a “Protect Our Green Spaces” page that has links to information on storm water management pond naturalization, common plant pests, tree identification and recommended native plants suitable in the Region. The Town has also posted a webpage about Emerald Ash Borer and Milton’s “Emerald Ash Borer: Tree Replacement and Treatment Strategy”.

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The Town has two programs that support tree planting and preservation on public and private lands: a Commemorative Tree Program (implemented by Town staff) and a Mature Tree Adoption Program (implemented by a local arboricultural service provider). The Town has initiated and coordinated several tree-related stewardship events over the past few years. These include annual Community Planting Days in various Town parks, channels and open space, and celebration of National Tree Day (September 21st), since it was first initiated in 2012.

Figure 7: Informational door hangers for residents regarding Emerald Ash Borer, Prunus black knot and young street tree care and maintenance.

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The Town is increasingly proactive in notifying local residents about significant tree removal and maintenance works in their neighborhoods, and engaging them in the replanting activities where possible. One example is the tree maintenance work along the Mill Pond Trails which was initiated in 2012. The Mill Pond Trails outreach included the release of a two page information sheet and a community planting event supported by a grant from TD Green Streets. The Town also has an on-line trails reporting form (for this area and all community trails) whereby users can report tree maintenance issues, as well as other trail related concerns or obstructions. The Town of Milton, in its Official Plan, supports outreach, engagement and partnerships related to forestry and forest conservation in its Official Plan (see Policy 2.3.3.1), and continues to try and integrate protected woodlots that are adopted by the Town into the surrounding community, and to integrate mature trees into new parks.

4.5.2. Halton Region

In southern Ontario, upper tier municipalities (in this case, Halton Region) tend to focus on forest assets, while the lower tier (in this case, the Town of Milton) tends to focus more on the management of individual trees and more sparsely treed areas (e.g., in Town parks and open spaces). The outreach and stewardship undertaken by the Town and the Region generally reflects this division of responsibilities. There are fourteen municipally owned and managed tracts of forest throughout Halton, with many of these being within the Town of Milton’s rural areas along the Escarpment. Six of these forests are also Environmentally Sensitive Areas (ESAs). Information about these forests is available on the Region’s website and includes maps and pamphlets providing an overview of the history and significance of these tracts. The Region’s website includes information on its woodland by-law (by-law 121-05), and on Good Forestry Practices, which are permitted under the by-law. To promote forest stewardship, the Region has a five-page guide for homeowners who purchase properties adjacent to ESAs. The text speaks to the value of ESAs, ways to avoid encroachment and negatively impacting the ESA, and also a map of the ESA in its land use context. The Region also supports a Woodland Stewardship Program (guidelines are available on the Region’s website) whereby interested landowners may be eligible for financial assistance from the Region for one, or more, of the following: development of a Forest Management Plan (for properties of at least 2 ha), purchase and planting of nursery stock (for properties of at least 2 ha), and development of a Tree Marking Services Plan (for woodlots of at least 0.5 ha). Another useful resource related to Milton’s urban forest provided on the Regional website is a list of recommended native plants for restoration or naturalization projects that provides basic habitat preferences, includes trees and shrubs, and also includes Carolinian species known to grow in the Region south of the Escarpment.

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4.5.3. Conservation Halton Although conservation authorities are often associated with the protection and management of water resources, they also recognize the importance of forested areas in their watersheds. Conservation Halton plays a major role in forest management and reforestation in their jurisdiction (which encompasses the entire Town of Milton), and provides a number of outreach and stewardship programs targeted specifically at forest management and reforestation. Examples include their Trees for Watershed Health program, Halton Forest Festival and the Hamilton-Halton Watershed Stewardship Program. Additional outreach and stewardship programs offered by Conservation Halton that are not specifically related to forests, but teach and encourage recognition of the value of the natural environment as a whole include BioBlitz Workshops, Natural Connections (a collaborative outreach initiative) and Conservation Awards of Excellence. These programs target both public and private lands, and include properties in both the rural and urban portions of their jurisdiction.

4.5.4. Other Potential Partners and Funding Sources The Halton Peel Woodlands and Wildlife Stewardship, which is a program of the Ontario Ministry of Natural Resources, provides a number of resources related to forests (e.g., Butternut tree recovery, how to locate a forester to manage your woodlot, lists of native trees and shrubs suitable for the area) and sometimes facilitates tree planting events in Milton and other municipalities within its jurisdiction. Historically, these resources have been targeted at rural landowners, however there are now some initiatives aimed at enhancing forest cover in urban residential areas. Their website also provides links to information posted on invasive forest pests and forest health management. Tree Canada supports tree planting on private and public lands in urban and urbanizing municipalities through its TD Green Streets Program. Grants of up to $15,000 are available to successful municipalities but matching funding from elsewhere is required. (Notably, in 2012 the Town of Milton was successful in obtaining such funding for its Mill Pond Naturalization project). Trees Ontario offers three different tree planting subsidies to private landowners, and typically works through agencies (in Milton it would be Conservation Halton) to administer this program. This program focuses on larger landowners with space to plant several hundred or several thousand trees.

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There are also a number of programs that would not be directly accessible to the Town, but could be accessed through partnerships with one or more local community group and/or non-profit organization. These include: •

• • •

Environment Canada has been, since 1995, supporting the EcoAction Community Funding Program which provides financial support to community-based, non-profit organizations for projects that have measurable, positive impacts on the environment, including protection and improvement of habitats. Evergreen is a non-profit organization based in Toronto that provides grants for schoolyard naturalization (Toyota Learning School Grounds Greening Program) and greening of public open spaces (Common Grounds Program) led by community groups. Tree Canada supports tree planting on corporate lands through its Corporate Greening for Carbon Credits Program and provides a carbon certificate to successful participants. The Association for Canadian Educational Resources (ACER) is a non-profit organization that offers a number of programs specifically designed to get youth engaged in activities related to monitoring and responding to climate change, including collecting data in forests and planting trees. They have specific resources for schools, teachers and communities designed to provide applied learning through established curricula in southern Ontario.

There are likely other local organizations involved in activities related to trees and forests in the Town in Milton, however further consultations and research would be required to seek these out.

Courtesy: Town of Milton

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5. Best Practices and Precedents This section of the Strategy presents best management practices and precedents from the scientific and technical literature, the urban forest management and arboricultural industries, and other North American municipalities. The purpose is to provide examples which may be adopted, emulated or modified by the Town of Milton in an effort to improve its own urban forest management activities. While efforts have been made to primarily select best practices from comparable municipalities, some examples from larger jurisdictions or those with different urban forest types have been included if they provide useful and readily applicable lessons for Milton’s urban forest program. The examples provided have been selected based upon identified needs facing Milton’s urban forest.

5.1. Understanding the Urban Forest: Tree Inventory and Asset Management 5.1.1. Tree Inventories

There are two common types of urban forest inventories. The first is a ‘tree-by-tree’ operation-focused inventory, which typically includes a range of data pertaining to individual trees on the landscape, and is most commonly used to organize data for municipal street and park trees. The second is a broaderranging ‘urban forest study’ inventory (e.g., i-Tree Eco), which aggregates data from randomlydistributed sample plots and extrapolates them to develop a ‘big picture’ view of the urban forest. The latter inventory type is useful for quantifying urban forest benefits and for understanding the general structure and distribution of the resource (e.g., estimate of canopy cover in different land uses, most common species, etc.). However, this type of study offers little to support day-to-day municipal operations, and staff cannot use its results to dictate arboricultural work or even to find discrete spaces for tree establishment. This is where the former system (an operation-focused inventory) is most useful. A tree inventory can include a wide range of data. The most useful attributes include: •

Tree Identification: Trees are typically given an identification number in an inventory database. The number can simply correspond to: (a) the order in which trees were assessed (basic), (b) a composite number reflecting municipal address, geographic sector and block number (good), or (c) a physical tree identification tag (optimal).



Location: Tree location in the database can be denoted by: (a) municipal address or block ID (basic), (b) tree points mapped through aerial photo interpretation (good), or (c) tree location coordinates and crown diameter polygons included in a GIS database (optimal). All levels of inventory should include a municipal address to facilitate the implementation of work orders. GIS mapping can greatly facilitate desktop exercises such as infrastructure project design or tree establishment planning.

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Location type description: A description of the tree habitat type (e.g., hardscape tree pit, lawn, etc.) can facilitate management planning by directing certain activities, such as watering or mulching, to the sites where they are most appropriate or necessary.



Species: This attribute is essential for assessment of urban forest structure. Trees should be identified to species level, botanical names should be used, and varieties and cultivars should be noted if possible.



Diameter at Breast Height (DBH): This is a standard attribute for assessing tree size and is typically measured at “breast height” or 1.37 m above grade.



Size and age: Attributes such as tree height, crown height, crown diameter and age class greatly facilitate maintenance planning and crew/equipment allotment, improve understanding of urban forest structure, and enable Leaf Area Index calculation, which is a better assessment of urban forest cover than canopy cover percentage.



Condition: Tree condition may be assessed through a variety of methods. The most basic condition assessment is an overall scale-based rating (e.g., good, fair, poor). Such a basic assessment may be insufficient to provide an accurate picture of a tree’s true condition. At a minimum, ratings should distinguish between canopy (leaf) and trunk condition. A higher level of detail assesses trunk integrity, crown structure and crown vitality individually. The optimal level assesses several components of stem and crown structure (e.g., root flare, stem, crown base, and scaffold branches) for a variety of indicators (e.g., cracks, growth deficits, wounds, decay, etc.) on an ascending, point-based scale. Such information can be used to schedule tree maintenance or inspection, as well as to develop a better understanding of tree risk and urban forest health, and structure. Querying a database with this level of data can also generate species profiles to guide future tree establishment decisions.



Pests and pathogens: Visible signs of pests, diseases or decay pathogens should be noted separately from general comments to enable more effective pest management and pest infestation response planning.



Work recommendations and priorities: Managing and assigning maintenance recommendations is one of the most useful aspects of a street tree inventory, and perhaps the most important component of the transition from reactive to proactive urban tree management. Including recommendations within the inventory increases efficiency and reduces costs by both enabling directed maintenance and reducing tree failures and associated liability. Recommendations should be assigned in a standardized manner (e.g., work code), and not in a general comments attribute field. An optimal inventory includes work recommendation codes and supporting comments, and prioritizes maintenance requirements on a time-based scale. Such an inventory can be queried to develop work lists and time, cost and materials estimates.



Risk assessment: An assessment of a tree’s risk potential is an effective means to reduce liability, prioritize work recommendations and improve service delivery effectiveness and efficiency. Rating risk also demonstrates a municipality’s commitment to fulfilling its duty of care to ensure public trees are maintained in reasonably safe condition. Tree risk assessment should

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be undertaken in accordance with ANSI A300 Part 9: Tree, Shrub and Other Woody Plant Management – Standard Practices (Tree Risk Assessment a. Tree Structure Assessment) and the companion Best Management Practices – Tree Risk Assessment published by the International Society of Arboriculture (2011). •

Conflict: Trees may grow into conflict with overhead utility wires, other trees, signs, structures, sidewalks and other infrastructure. A basic inventory will note the presence or absence of conflicts, while more advanced levels of assessment will note the type of conflict and, in order to ensure consistency and facilitate future management, list each type of conflict with an alphabetical code.



Plantable spaces: In addition to data concerning existing trees, locations which are potentially suitable for tree establishment can be identified, graded for suitability (e.g., marginal, good, optimal), mapped, and used to prioritize planting activities.

Table 3, below, compares key inventory components for “basic”, “good” or “optimal” tree inventories. Table 3: Attributes of varying levels of tree inventory.

Location Location Type Description Species Diameter (DBH) Crown Diameter (approx.) Crown Height (approx.)

Basic

Good

Optimal

Municipal Address or Block

Points through aerial photo interpretation

Geographic coordinates as part of municipal GIS system

-

-

-

-

-

Tree Height (approx.)

-

-

Tree Age Class

-

Condition

Scale-based

Pest/Pathogen ID

-

Work Recommendations

-

Work Priority

-

Risk Assessment

-

Infrastructure Conflict Plantable Spaces

Yes/No

Scale- or point-based -

Scale or point-based, by tree component part

Using formal risk rating system Descriptive

-

Code-based GIS record

Comments Database Management Data Collection Method Tree Types Inventoried

Computerized Paper or handheld device Street trees

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GIS and Asset Management System Handheld device with GPS capability Street/park trees and woodlands

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5.1.2. Examples of Successful Tree Inventories The Town of New Tecumseth, Ontario The Town of New Tecumseth, a predominantly rural municipality north of Toronto, undertook a complete street tree inventory project in the summer of 2009 within its three urbanized communities (Alliston, Tottenham and Beeton). This inventory of over 5,000 street trees is GIS-based and includes common size and species attributes; highly-detailed condition assessments; and code-based work recommendations with priority ratings, which can be queried to generate individual and street-based work orders. Unlike in most municipalities, all street trees are tagged to facilitate identification in the field. Tree tags are installed using a specialized tool at a height sufficient to prevent tampering or dislocation. Should tags be removed, trees can also readily be identified by municipal address and location coordinates. The City of Kitchener, Ontario Kitchener maintains an inventory of over 47,000 street trees. The inventory is GIS-based, and was developed to be fully compatible with the i-Tree inventory analysis software suite. A variety of condition and work order attributes are included, using standardized comments to facilitate analysis. The inventory has been used to generate a cost-benefit analysis of the city’s urban forest, and was an important component of the city’s Emerald Ash Borer management strategy. It will also be integrated into the city’s work order management system. The City of London, Ontario London undertook an inventory of 123,359 street and 32,101 park trees in 2002, and regularly updates the system to reflect spring and fall plantings as well as the removal of hazardous and dead trees. Findings suggest that 33% of London’s trees are maples. The inventory assists the city’s Forestry Group in its year-round maintenance program as well as tree establishment planning. The city’s street tree map is available online through the CityMap application. Residents can view basic data about street and park trees, including species and diameter. Town of Oakville, ON Oakville currently operates Azteca Systems, Inc. CityWorks, an ESRI GIS-compatible digital asset management system which includes basic information regarding the Town’s trees. The Town’s urban forest management plan recommended that basic GIS information concerning Town’s trees be made available online for public use, and that the system be configured to track tree survivorship, which will aid in future tree species selection for establishment on municipally-owned property. The plan also recommended that the system be configured to provide an annual summary of all risk trees to be inspected.

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The City of Pittsburgh, Pennsylvania, USA The City of Pittsburgh conducted an inventory of 30,538 street trees in 2005, comprised of 134 species and 60 genera. The stated objectives of the street tree inventory project were to: 1. 2. 3. 4. 5. 6.

Identify hazardous conditions; Provide accurate data for the City’s operational and capital budgeting process; Prioritize work; Enhance efficiency of maintenance operations; Permit proactive management of disease and pest infestations, and; Establish basis for compensatory value.

Findings from the inventory resulted in over $8 million in recommended maintenance work such as pruning and removal, and were incorporated into a 7-year management plan. The City allows the public to explore the street tree inventory database online, providing access to all inventory attributes. Users can zoom in on a map of Pittsburgh and click on individual tree points, which then provides them with a summary report about the selected tree.

5.1.3. Urban Forest Asset Management

Urban forest asset management is different than, but closely related to, tree inventory collection and maintenance. In fact, both systems can be managed by the same set of tools – preferably GIS-integrated software. The difference is that while a tree inventory system contains attribute data pertaining to individual trees or groups of trees, an asset management system integrates these data into the broader municipal operating context. An asset management system is generally considered a combination of software tools and processes that facilitate the management of a variety of corporate assets, such as infrastructure, facilities or fleet vehicles. Digital asset management systems can be shared across an entire municipality, and can assist with physical asset selection, inspection, maintenance and management requirements, as well as tracking work order history, costs and contract provisions. By managing assets across the Town using a shared system, Milton could improve resource utilization and performance, reduce capital costs and asset-related operating costs, extend asset life and ultimately improve returns on investment. While recommending the implementation of a corporate-wide asset management system is beyond the scope of this strategy, the Operations division and/or its contractors should implement a process to regularly update tree inventory data during the course of day-to-day arboricultural operations. This can be undertaken at minimal cost as part of day-to-day operations. Ideally, the database entry for each tree should be updated when a tree is maintained, removed, or impacted by development and construction. A new entry should be created each time a new tree is planted. This would enable the Town to build up a long-term profile of the urban forest to incorporate into ongoing management planning decisions, enable accurate budget forecasting for future maintenance programs, and proactively plan tree removal and replacement activities.

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The Town already inventories new park trees in an asset life-cycle based approach, whereby the “Acquisition Year”, “Purchase Price”, “Useful Life Expectancy in 50 Years” and “Replacement Year” are recorded and tracked. This information is used to establish prices and standards and allows for an objective review of future replacement costs and budget requirements. Other Town-owned trees can and should also be incorporated into a similar life-cycle based asset management structure.

5.1.4. Canopy Cover Assessment

A common method to describe the extent of the urban forest is to measure the amount of canopy cover provided by trees. Canopy cover is a two-dimensional measurement of the horizontal surface area of the forest as seen from a ‘birds-eye’ view. It is a popular metric because it is readily understood, but it is limited in so far as it does not capture other important aspects of the urban forest, such as species diversity, urban forest structure (i.e., size and age ranges) or condition, level of maintenance, or level of community engagement. Some jurisdictions use canopy cover percentage as a comparative metric to assess the success of their urban forestry programs in relation to other comparable jurisdictions, or set canopy cover targets as the main objective of management. However, setting overly ambitious canopy cover targets can unduly focus urban forest management on tree planting at the expense of other equally important strategic initiatives, such as maintenance and monitoring. Furthermore, it fails to estimate the potential canopy cover or the resources required to achieve this potential. Canopy cover can also be problematic because there is no accepted standard method for measuring it. Different methods can result in different estimates for the same jurisdiction with different levels of accuracy. Therefore, canopy cover assessments should be understood to be only estimates unless every single tree and wooded area has been mapped and assessed. In spite of some shortcomings, canopy cover remains a readily understood and commonly-used urban forest metric. If assessed, it should be measured in a consistent way so that changes in its status and extent can be tracked. There are currently several approaches used to assess canopy cover: •

i-Tree Eco: This approach is based on data extrapolated from plot-based assessments and is readily replicated but has a fairly large margin of error, which varies depending on the number of plots in a given jurisdiction. Such studies have been completed in several Canadian municipalities, including Calgary, AB and Oakville, ON. These studies are a fairly cost-effective way of generating data for estimating canopy cover, urban forest species diversity and structure, and eco-service values. However, this method tends to be less accurate than the following two methods.



UTC (Urban Tree Canopy): This method involves analysis of high-quality satellite imagery and can provide fairly accurate estimates of canopy cover, as well as plantable spaces, but requires powerful computing and expensive software to separate trees and shrubs from other land use covers within an urban matrix. This has recently been used by the City of Toronto and the Region of Peel in collaboration with experts from the United States Department of Agriculture (USDA) and the University of Vermont. As GIS tools and technologies evolve, this option may be more readily available to smaller municipalities like Milton, but current costs are prohibitive in relation to the value of the information provided.

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Orthorectified Aerial Photos and GIS: Some municipalities have used a combination of aerial photo interpretation and GIS mapping / analysis tools to obtain canopy cover estimates. This involves combining mapping of treed natural areas with point count data about trees in the urban matrix to establish an overall estimate of canopy cover. This mapping can also be used to identify plantable spaces if the point count data is sufficiently detailed and comprehensive. The level of accuracy depends on the extent to which the jurisdiction has been sampled, and the quality and currency of the available air photos. Newly-available tools such as i-Tree Canopy have reduced the costs of this type of assessment.

A canopy cover study is not currently recommended for Milton. The Town’s rapid pace of growth means that any assessment will not remain current for long, and will not provide meaningful metrics or management targets. Given current resource considerations and other management priorities, determining the Town’s potential canopy cover is also not a high-priority action at this time, but such a study could be pursued as part of a subsequent urban forest management strategic planning horizon.

5.2. Caring for the Urban Forest 5.2.1. Departmental Coordination

In virtually all municipalities tree care is a responsibility shared by multiple departments. However, the division of this responsibility varies depending on the individual municipal structure, the size and the extent of the urban forest, and the municipality’s commitment to urban forest care. To support proactive care and maintenance of the urban forest, management and staff from all departments and outside agencies and authorities must recognize that trees are a valuable municipal infrastructure component, even if they are not formally recognized as municipal assets. As such, all departments which may be involved with tree-related issues must bear at least some responsibility to ensure that they are managed and maintained effectively and sustainably.

5.2.2. Service Delivery

Urban forest management in Ontario, with few exceptions, is conducted using the model of joint municipal and contracted service provision. This model is applied in cities such as Windsor, Hamilton, Oakville, Mississauga, London, Toronto, and Burlington. The key variable is the relative distribution of specific operations between contractors and staff. In most examples, municipal staff and contractors share the tasks of routine maintenance such as pruning and tree removals. Planting is often conducted as part of capital projects and development, with additional infill planting undertaken by the municipality or contractors by tender. However, some smaller communities rely wholly on contracted service provision. Perhaps one of the most effective examples of this service provision model is the City of Brantford. The City’s urban forest management staff is comprised of one urban forestry coordinator and one technician, who supervise the maintenance or inspection of approximately 60,000 trees on a relatively short five year pruning cycle and the annual establishment of approximately 900 trees, and who work with other City staff to address issues which may affect the urban forest. The operating budget of Brantford’s forestry division of Parks and Recreation (under the Engineering Department) is approximately $600,000 annually. Town of Milton Urban Forestry Management Strategy

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5.2.3. Proactive Maintenance of Publicly-owned Trees

Over the long term, a planned and cyclical approach can provide significant cost savings over reactionary pruning and tree maintenance, particularly if the pruning cycle averages around five years (Miller and Sylvester, 1981). A shorter cycle (i.e., five to eight years) reduces the number of resident service requests (which are costly to fulfill as maintenance crew time is spent travelling from site to site, rather than progressing through a linear work area). Furthermore, systematic tree maintenance enables earlier detection of pest and other plant health issues, resulting in improved overall urban forest condition. Many municipalities inspect and maintain street trees in a scheduled, cyclical manner. This is termed “grid”, “block” or “cyclical” pruning. Some municipalities distribute annual pruning activities across the entire area, pruning a portion of every neighbourhood each year, while others maintain all of the trees in one or two areas of the city and move elsewhere in the next phase of the cycle. The main benefit associated with the first approach is a reduced perception of tree maintenance crew presence in a given section of the municipality at any point in the pruning cycle. For example, if a given neighbourhood has 1/5 of its trees pruned in one year of a five-year pruning cycle, the crew will be present in that neighbourhood for less time per year than if all of that neighbourhood’s trees were pruned at once. However, that crew will return to the same general area every year, whereas utilizing the latter approach, they would not return again until a new cycle begins. A sampling of municipalities across North America found that urban forest inspection and pruning intervals vary widely between municipalities, from short five year cycles to much longer 16-year cycles. A shorter cycle does not necessarily imply better management. Longer cycles can be supported by an urban forestry program which is dedicated to planting diverse, high-quality nursery stock in good habitat, resulting in fewer short-term maintenance requirements. In a municipality like Milton, which contains both a densely-populated urban area and rural settlement areas, it is challenging to ensure that all street trees are maintained in a cyclical manner. Similarlystructured municipalities with cyclical pruning programs will typically implement the proactive cycle in their urban areas, while undertaking reactive request-based or as-needed maintenance in the rural areas.

5.2.4. Young Tree Maintenance

Pruning during the ‘formative years’ of a tree’s life, which can be conducted from the ground at little cost, is one of the best possible investments in the future urban forest. Proactive and early pruning provides trees with good form which can be maintained throughout their lives, thereby lowering the risk of future component failure and reducing liability and long-term arboricultural maintenance requirements.

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Research and experience in leading municipalities suggests that immature trees should generally be pruned about three times within the first ten years after planting. Young trees should be pruned to ‘train’ them towards good structure. Typically no more than five to eight pruning cuts are usually required during each pruning round. Young tree pruning can be conducted from the ground using secateurs and pole pruners. Climbing and use of aerial lift devices will typically not be necessary, and a large number of trees can be pruned per unit time. Given the fast growth rate of young trees in good growing sites, it is difficult to incorporate young tree pruning into a cyclical pruning program, and longer cycles will lead to backlogs in structural pruning requirements. Furthermore, the type of resources required make it inefficient to integrate young tree pruning with block pruning as there is no need for arborists equipped with aerial lift equipment or wood chippers to tend to small trees reachable from the ground.

5.2.5. Tree Risk Management

Tree risk assessment and mitigation are becoming increasingly recognized as a critical component of urban forest management. The key to effective tree risk management lies in an operational policy that coordinates inspection, mitigation and proactive planning in order to improve safety and reduce risk, uncertainty and liability. A dedicated policy will set minimum standards for risk assessment and documentation, resulting in consistency of assessment and sustained resources for inspection over the long term. Key components of an effective risk management policy or strategy include: •

• • • • • • •

A policy or mission statement framing the scope of the policy (including which trees/areas are included), assigning responsibility, setting goals and outlining a realistic Standard of Care statement; Determination of acceptable risk, outlining what the Town considers an acceptable threshold for risk of tree failure; Minimum levels of training and qualifications of risk assessors, outlining the expected credentials that tree risk assessors should possess; Frequency of assessment, outlining how often publicly-owned trees in different settings (e.g., trails, high-traffic streets, new communities) are to be inspected for risk; Management options, outlining what arboricultural treatments the Town will consider for implementation to mitigate risk, such as pruning, cabling, bracing, or removal. Record-keeping protocols, to enable tracking of inspections and mitigation actions; Strategy funding and/or partnerships, to identify expected costs and anticipated sources of funding to enable the implementation of the strategy, and; A strategy for program assessment and reporting to enable adaptive management and ongoing improvement.

A comprehensive risk management policy will also include a protocol for post-storm emergency response, including prioritized inspection and maintenance areas.

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Recent advances in tree risk assessment have given rise to new levels of risk assessment training and qualification by bodies such as the International Society of Arboriculture. Local arboriculture contractors should be consulted and encouraged to seek advanced tree risk assessment training and ultimately, such qualifications should be required components of tree maintenance contracts. Tree risk mitigation is an important practice and one that can extend the life of a tree that might otherwise be considered a risk. Practices such as cabling and bracing, if performed correctly and managed appropriately, can greatly reduce the risk presented by certain aging trees while maintaining the environmental benefits that such trees provide. Milton should work towards implementing such an approach, particularly in parts of the community where older trees may require such management techniques.

5.2.6. Pest and Disease Management

Reducing the vulnerability of the Town’s urban forest to pest and pathogen stressors will require the implementation of a wide range of urban forest practices, including: • • • • •

Plant Health Care: site-appropriate tree species selection, young tree pruning, cyclical pruning, watering, mulching, fertilization where required; Improving tree habitat: increasing soil volumes, improving soil quality, reducing above- and belowground competition for space and resources; Diversifying the urban forest: establishing underutilized and new native and non-invasive tree and shrub species; Improving knowledge and understanding of the urban forest: conducting a public tree inventory and increasing monitoring/inspection frequencies; Pest-specific management: Development and implementation of targeted strategies to mitigate the effects of specific insect pests or pathogens, including use of treatments when necessary and appropriate.

Plant Health Care (PHC) Trees in urban areas face many stresses, making them increasingly susceptible to pests and diseases. Stressed trees are also more prone to structural problems, which may be further compounded by long intervals between inspection and maintenance, as well as inadequate cultural practices. A coordinated approach to manage pests, diseases and invasive species, maintain an optimal growing environment, and promote good tree form and structure is called Plant Health Care (PHC). PHC also recognizes the importance of other landscape plants such as shrubs and grasses, and the positive or negative influence these plants may have on tree health.

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Integrated Pest Management (IPM) Integrated Pest Management (IPM) is a similar concept, which aims to assess and control pest populations through a combination of early detection, cultural practices and pesticides, if required. The six key components of an IPM program include: 1. Acceptable pest levels: This principle recognizes that eradication of pest and pathogen species is generally impossible and often undesirable. An effective IPM program will establish an acceptable threshold, above and beyond which control actions will be undertaken. 2. Preventive cultural practices: Methods such as appropriate species selection, maintaining vitality (e.g., watering), pruning, etc. are the first step towards maintaining acceptable pest population levels and reducing pest pressure. 3. Monitoring: Regular and comprehensive inspection and identification of pest and pathogen pressure is a critical step of effective pest management, enabling rapid response if necessary. 4. Mechanical controls: Should pest and pathogen levels reach unacceptable levels, mechanical controls such as pruning, trapping, barrier installation or the like should be investigated and, if viable, implemented before resorting to other methods. 5. Biological control: Natural processes, such as beneficial insects or microorganisms that target the undesirable pests, should be considered prior to synthetic pesticide use. 6. Reasonable pesticide use: If all other methods fail to achieve acceptable pest levels, insecticides should be considered. Pesticide use should focus on targeting specific pests at the appropriate life stage; broad-spectrum pesticides should be avoided if at all possible. Furthermore, efforts should be made to reduce the likelihood of pests developing resistance to the active ingredients used in the control program. Comprehensive PHC and IPM programs, coupled with cyclical maintenance pruning, are critical to maintaining and promoting a healthy, safe and functional urban forest.

5.2.7. Pest and Disease Management - Components of an Emerald Ash Borer Strategy

It is recognized that Emerald Ash Borer is currently the most pressing urban forest health management issue in Milton, and will likely require the allocation of a significant amount of management resources over the next decade or beyond. As such, this subsection presents the key components of an effective long-term strategy for managing the effects of this pest, and should be used as a guide for the development and implementation of a targeted EAB management approach. Key components of an EAB management strategy (development and implementation) should include: • • • • • •

Ash tree inventory, including significant trees for potential treatment; Survey methodologies, especially branch sampling; Management zones; areas where differing types/scheduling of management may be applied Management strategies, including removal and replacement, injection and pre-emptive removal; Communication and public education, and; Cost analysis and budget.

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Ash Tree Inventory Knowledge of the location, size and condition of ash trees is crucial to the effective management of an EAB infestation. An ash tree inventory will enable the Town to prioritize survey and management activities depending on the distribution, condition, and potential risk associated with ash trees, which typically die within 2 to 3 years of infestation. An ash tree inventory (extracted from the 2009 tree inventory data) is currently available for the Town of Milton and includes 3,940 trees. Survey Methodologies A number of survey methodologies can be implemented individually or in combination to facilitate the detection and delimitation of EAB infestation, especially in its early stages. The most commonly-applied and successful of these is the Canadian Forest Service (CFS)-developed grid-based branch sampling technique. Using this technique, a one km grid is overlaid on a map of the municipality. A radius of 250 m is drawn around each grid intersection point to create sample plots. All ash trees in the inventory are displayed on the map. A field crew is then dispatched to each plot or to random plots to collect ash branch samples. Information such as species, DBH, and height are recorded along with any visual signs of EAB. Ten or more ash trees are selected, starting from the center of each plot. Sample trees can be selected at random, or based on criteria such as condition or size. Two branches are removed from each tree using a pole pruner (mid to lower crown, south aspect). Branches should be a minimum of 5-7 cm diameter and at least 50 cm long. Branch samples are labelled on the cut ends. It is estimated that 25 mid-sized trees (50 branches) can be sampled per day by a two-person crew. Branch samples are then taken to a laboratory or other facility where the bark is removed to expose the phloem. Branch samples are typically secured in a table vice and the bark is removed using a draw knife. Once the bark is removed, thin slices of phloem are shaved off to expose larvae/galleries. All signs of EAB are recorded, including the number of larvae, number of galleries (old and new), number of eggs, etc. The inspected branches are then collected into two categories; infested and not infested. If branches are inspected in the fall, the shavings of phloem should be very thin (1mm), to ensure that no larvae or galleries are missed. Thicker shavings are possible in the spring when larvae have matured. Experience suggests that more larvae/galleries have been found on the top of branches, and that visual and hidden evidence of infestation can typically be found more often on the south and west facing sides of infested ash trees. Other methodologies including visual assessment, tree climbing, destructive sampling, and detection trees are also possible, but are less suited to wide implementation as part of a targeted EAB management strategy. Visual assessment or canopy inspection through climbing are better suited to implementation during routine grid pruning and tree maintenance. Management Zones Due to resource constraints, the Town may need to prioritize areas for more intensive surveying and implementation of management strategies upon identification of an EAB infestation. This is likely to

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include the Central Business District and areas with a greater population of maturing ash trees, rather than smaller trees or where ash is less prevalent. However, grid-based branch sampling should be conducted across the Town. Should infestation be confirmed and the Town chooses to implement management strategies, resource constraints will require that specific areas, or ash trees with certain attributes, be prioritized for management. A number of factors, such as local tree diversity, community perception of individual trees or trees of certain size/age, risk potential, and others, will determine priority areas or trees for priority management. Management Strategies It must be recognized that no management strategy will result in the prevention or elimination of an EAB infestation. However, several management strategies are available to manage cost and risk and save important ash trees. The range of potential management options includes: • • • •

The ‘Do Nothing’ Approach, whereby only dead trees are removed to mitigate risk; Visual inspection, removal and replacement of only dead/diseased trees; Proactive removal and replacement of ash trees before and following infestation, and; Tree injection of significant ash trees.

The cost of implementing these approaches will vary widely depending upon the number of trees affected, the intensity of management, and other factors. As part of EAB management, removed trees should be replaced with suitable non-ash tree species. The objective of tree replacements should be to establish trees with low pest susceptibility and to increase urban forest diversity. All removed infested and non-infested ash trees should be processed and disposed of in a manner that eliminates host suitability for all EAB life stages. The expected influx and surplus of wood material from dead ash trees can potentially be sold to market, or may complement the Town’s supplies for its tree establishment and mulching activities. It can even be given away to residents for use in gardens once it is well composted (2+ years composting time). Dispensing mulch is a common practice in many municipalities, and is often a key component of community environment days and other similar activities. Communications and Public Education Effective management of EAB in Milton will require the timely communication of: • • • • • • •

Identification of ash trees and EAB signs and symptoms; The threat of the Emerald Ash Borer; The status of the infestation; Planned and proposed management activities, including systemic pesticide injection (if undertaken); Reporting procedures for suspected EAB infestation; The responsibilities of residents to monitor their own trees and manage pests, and; External resources including identification guides, management strategies, agencies and scientific publications.

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Good public communication may help encourage cooperation such as reporting possible infestations, and may alleviate potential anxieties regarding the threat of EAB or possible insecticide usage. Conversely, poor communication may erode support for an EAB management program, increase losses of trees and their associated benefits, and lead to a general misunderstanding or mistrust of the agencies involved. Communications tools should include the internet (a dedicated webpage), media and paid advertising, public information sessions, printed materials (leaflets and door hangers in affected areas), and door-to-door outreach. Cost Analysis A detailed cost analysis, which should include the costs of surveying and monitoring, potential long-term management strategies and the potential loss of tree benefits, will enable decision-makers to select an appropriate management strategy and plan future resource allocations.

5.2.8. Emerald Ash Borer Management in Other Jurisdictions Most communities affected by Emerald Ash Borer in Southern Ontario and beyond have begun to implement management strategies to address the effects of the infestation, which is now widespread throughout most of the Region. Management strategies vary widely, from largely removal and replacement-focused activities (both preemptive and reactive), to more treatment and protection-focused approaches. The key components of several municipal EAB management strategies are compared to Milton’s current strategy and presented in Table 4, below.

Aerial view of a “New Milton” community. Courtesy: Mattamy Homes.

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Table 4: Comparison of municipal Emerald Ash Borer management strategies in Ontario. Oakville Ash Inventory

Complete

Street, Park, Woodlot 14,500 Managed Ash (street/park); Tree Population ±44,000 (woodlots) Treatmentfocused Approach Summary (streets/parks), removal (woodlots) 5,450 (75% of # (%) Protected/Treated treatable ash canopy) Ash Trees Considered

Treatment Criteria

>20 cm DBH, good condition

# (%) to be Removed

8,700 (25% of ash canopy)

Notes

Extensive public outreach campaign through Canopy Club

Toronto Partial

Street and Park

Mississauga Complete (streets and significant parks), woodlot edges/trails ash assessment Street, Park and Woodlot Edge

Kitchener

Markham

Milton

Complete

Complete

Complete (“Urban Milton”)

Street and Park

Street and Park

Street

±83,000 (street and park)

23,311 (street) ±23,000 (park)

6,428

16,738

±4,000

Removal and replacement, some treatments

Removal and replacement, some treatment

Removal and replacement, some treatment

Treat all healthy City trees, remove others

Removal and replacement, some treatment

8,000 (10%)

±8,000 (17%)

1,415 (22%)

Total TBD (370 in 2014)

860 (21%)

High value, >30% dead, good health

>20 cm dbh, good >30 cm dbh, condition, healthy location

>75% foliage, >20 cm dbh

Trees >20 cm and in good condition

75,000 (90%)

±38,000 (83%)

10-year program; 860,000 ash trees across City, woodlots to be managed as required

Town of Milton Urban Forestry Management Strategy

10-year program, 70,000 trees in woodlots and edges; edges to be managed

Total TBD (6,000 in 2014) Funding approved Treatment to be to 2022 for determined removal and based on health injection, no assessments; stumping/planting replanting to funding beyond commence in 2018 2015

5,013 (78%)

53

2,800 (70%) 6-yr program including replacement for each street tree removed due to EAB. Annual review.

5.2.9. Tree Protection

A number of municipalities in Southern Ontario recognize that their policies require specific guidelines, standards and specifications related to tree protection to ensure effective tree protection ‘on the ground’. This section presents examples from several of these municipalities, including tree protection by-laws and planning policies. City of Burlington, Ontario The City of Burlington has had a public tree protection by-law since 1975, which is currently being updated. Under the 1975 by-law: • • • •

A permit is required from the City Arborist to mark, damage or destroy a tree on City lands; A permit is required from the City Arborist to spray, prune or plant a tree on City lands; Specifications are provided for minimum distances from nearby infrastructure, and; A fine of $200 is levied for damaging one tree; additional penalties not to exceed $25.

Key forthcoming changes include bringing it into conformity with the 2001 Municipal Act, refining definitions, increasing penalties and clarifying the City’s position on care of trees whose trunks are shared with private property. Trees protected by City Tree by-law 19-1975 must be protected from adverse impacts caused by construction activities through the application of tree protection measures. In February 2009, the City implemented Specification No.SS12 – “Tree Protection and Preservation”, to protect “trees not designated for removal for all works within the City of Burlington’s road right-of-way.” Such works typically consist of road and curb reconstruction and below-ground utility (e.g., sewer, hydro, gas) works. Specification No.SS12 was modeled on many of the standard specifications applicable in the Town of Oakville and the City of Toronto. The specifications set out in this policy are considered the standard specifications for tree protection measures whenever such measures are required by the City, in every instance where construction activities may result in damage to trees. For the purposes of this standard, a tree is understood to include all above and below-ground components. Higher standards than those outlined in the policy may be imposed when it is determined that the size, variety, location and health of a tree warrant doing so, or any circumstances surrounding the construction may pose a particular hazard to the tree. Less stringent standards may be applied if approved by a Qualified Tree Consultant (i.e., a certified arborist or landscape architect). Specification No.SS12 outlines standards for: • • • • •

Tree Protection Zone (TPZ) size based on trunk diameter at breast height (DBH); design and materials of tree protection barriers; procedures for tree removal and relocation; procedures for required works within TPZs including root pruning; and, guidelines for tree repair after physical damage.

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The specification also enables the City to hold securities against tree damage and mortality for up to two years from the date of final inspection of the construction project. Specification No.SS12 recognizes the importance of a tree’s Critical Root Zone (CRZ), which extends beyond the TPZ and considers the area where important structural, transport and fine feeder roots will likely be present. Works are allowed within this area provided that certain tree preservation methods, such as root pruning to a minimum depth of 300 mm at a maximum of 300 mm from the edge of excavation to prevent root tearing. Table 5: Minimum Tree Protection Zones and Critical Root Zones, City of Burlington. Trunk Diameter(DBH)

2

Tree Protection Zone (TPZ) Minimum Protection 3 Distances Required

Critical Root Zone (CRZ) 3,4 Distances Required

1.8 m 2.4 m 3.0 m 3.6 m 4.2 m 4.8 m 5.4 m 6.0 m

1.8 m 4.0 m 5.0 m 6.0 m 7.0 m 8.0 m 9.0 m 10.0 m

50 cm ht.

Varies

-

Blvd. Width

-

Min. 1.75 m

Blvd. Curb Setback Curb Face Sidewalk Setback

1.5 m

80 cm

1.5 m (low-speed), 3.0 m (high-speed) 1.5 m

1.5 m

1.0 m from walk

0.75 m

Driveway Setback Ditch Setback Building Setback

1.5 m (large tree), 1 m (small tree) -

Overhead Clearance

Min 1 m from o.h. utils; 5 m from streetlights,

Utility Clearance

1.5 m hydrant, 1.5-3 m hydro transformer

Tree Spacing

Large trees: 7-12 m, small trees: 5-7 m, conifers: 4-8 m

Hard Surface Plantings Min. soil volume Guiding Documents

Town of Ajax Design Criteria

1.5 m 1.5 m 3.0 m Plants