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How Does Your Garden Grow: Soil Health Analysis Student Investigation- PHYSICAL SCIENCE In this lab exercise, you will analyze soil to determine its overall quality. In your groups, you will become experts in one aspect of soil science (chemistry, biology or physical science) and be responsible for sharing your conclusions with the class.

Objective: To measure physical properties of local soil. Materials: -

Plate or weigh boat Balance large graduated cylinder (100-500 mL)

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Pre-Lab Discussion: Answer the questions below. What services do soils provide to society?

What does it mean to have “healthy” soil?

Soil Characterization Guide Magnifying Glass Ringed Soil Sample Plastic Wrap Distilled water

PROCEDURES: READ ALL DIRECTIONS BEFORE BEGINNING. (Adapted from USDA Soil Quality Test Guide)

PART A: Soil Characterization

Part 1: Soil Structure 1. Obtain a plate or large weight boat of soil. You will work with this sample for the entirety of Part A. 2. Use the “Structure” Soil Characterization Guide to identify soil as granular, blocky, platy, single grain or massive. 3. Record your data in the Soil Physical Science Data Table.

Part 2: Soil Texture 1. Follow the “Texture by Feel Procedure” in the Soil Characterization Guide to characterize soil texture. 2. Record your data in the Soil Physical Science Data Table. PART B: Soil Infiltration Rate 1. Take the 6-in ring filled with soil. 2. Line the soil surface inside the ring with plastic wrap, completely covering the soil and the ring. This prevents disturbance to the soil when adding the water. 3. Use a graduated cylinder to measure 450 mL of distilled water. 4. Pour the water into the plastic lining. It should form 1in of water. 5. Remove the plastic wrap and record the time it takes for the water to seep into the soil. Stop timing when the surface is just glistening. 6. Record your results in the Soil Physical Science Data Table. 7. Repeat steps 2-6 on the same soil sample. STEP 4:

STEP 5:

Clean up all lab materials and listen for further instructions from your teacher.

DATA: Soil Physical Science Data Table

Soil Structure

Soil Texture

Infiltration Rate 1

Infiltration Rate 2

(seconds)

(seconds)

Average Infiltration Rate (seconds)

DATA ANALYSIS: Soil Physical Science Use the Soil Physical Science Background Cards and the data you have collected over the past class to answer the following questions.

Soil Characterization: 1. What is the significance of structure and texture? (Why is this data useful- what could it tell you)

2. Describe the soil structure. How will this soil’s structure affect the soil quality? Describe 2 specific ways.

3. Describe the soil texture. How will this soil’s texture affect the soil quality? Describe 2 specific ways.

4. What conditions, specific to this soil site, do you think contributed to the soil structure? (ex. Regular use of machinery, such as tractors, results in soil compaction.)

Soil Infiltration Rate: 5. What is the significance of infiltration rate? (Why is this data useful- what could it tell you)

6. What is the difference between your first and second infiltration reading? Why do you think you measure infiltration twice on the same soil?

7. Calculate the average infiltration rate. How will this rate affect soil quality?

8. What conditions, specific to this soil site, do you think contributed to the measured soil infiltration rate?

General: 9. Based on your data, evaluate the overall quality of your soil. Is it “healthy?” Why or why not? Use specific data to support your conclusions.

10. What sources of error are present in your data? Rank your confidence in the data’s validity (high, medium, low) and explain your ranking.

11. What additional data or information would be helpful in evaluating overall soil health? Give at least 3 additional pieces of information and explain why they would be helpful.