EQ 3: How are soils tested for quallity?

EQ 3: How are soils tested for quallity?

Obj: Students explore and describe various methods for testing soil and water

Activity: Soil NPK test and Dissolved Oxygen test

Directions: 

Extraction Step

1. Fill the round extraction tube to the 30ml line with distilled water.

2. Add 2 Floc Ex tablets. Cap the tube and mix until the tablets disintegrated.

3. Remove the cap. Add one heaping teaspoon of soil.

4. Cap the tube and shake for one minute.

5. Let the tube stand until the soil settles out. The clear solution above the soil will be used for nitrate, phosphorous, and potassium.


Nitrogen

1. Use the pipet to transfer the clear solution above the soil to a test square tube until it is filled to the shoulder.

2. Add one Nitrate WR CTA tablet (3703A). Cap and mix until the tablet disintegrates.

3. Wait 5 minutes for the color to develop. Compare the pink color of the solution to the Nitrogen Color Chart.

L = 40 lb. A/6" soil
M = 160 lb A/6" soil
H = 320 lb A/6" soil


Phosphorous

1. Use the pipet to transfer 25 drops of the clear solution above the soil to a square test tube.

2. Fill the tube to the shoulder with distilled water.

3. Add one Phosphorous Tablet (5422A). Cap and mix until the tablet disintegrates. Wait 5 minutes for the color to develop.

Compare the blue color of the solution to the Phosphorous Color Chart 

L = 8 lb. A/ 6" soil
M = 20 lb A/6" soil
H = 64 lb A/6" soil

Potassium

(see booklet)


Dissolved Oxygen Test

Short Form Instructions

1. Fill Water Sampling Bottle (0688-DO)

2. Add 8 drops of Manganous Sulfate Solution

3. Add 8 drops of Alkaline Potassium Iodide Azide.

4. Cap and mix.

5. Allow precipitate to settle.

6. Use the 1.0g spoon to add Sulfamic Acid Powder or add 8 drops of sulfuric acid, 1:1 (6141WT).

7. Cap and mix until reagent and precipitate dissolve.

8. Fill test tube to the 20mL line.

9. Fill titrator with Sodium Thiosulfate.

10. Titrate until sample color is pale yellow. DO NOT DISTURB

11. Add 8 drops of Starch Indicator.

12. Continue titration until blue color just disappears and solution is colorless.

13. Read results in ppm dissolved oxygen.


Resources for Soil Testing Kits 

Answer the following questions about soil tests using these websites:


Where does one go to obtain a soil test?

UMASS Soil Testing

What are the indicators of soil health in turfgrass?

How do results of standard soil tests get interpreted?

Why do trees and shrubs sometimes need a pH above 7?

How does lead in soil show up in a soil test?


Standard
Soil Test: Results and Interpretation (General)

Lead in Soil:
Results and Interpretation

Soil
Test: Results and Interpretation (Turfgrass)

Soil
Test: Results and Interpretation (Grapes)

Trees
and Shrubs Adaptable to pH 7 and Greater

Moss in Lawns