How to take a soil sample

Why do we take soil samples?

The purpose of taking soil samples to be sent to regular state laboratories is to determine the need for lime, nitrogen, phosphorus and potassium. Other nutrient deficiencies may also be determined. Soil samples may be sent to specialized laboratories to determine load-bearing or drainage capabilities by chemicals or insects or disease present.

When should soil samples be taken?

Soil samples may be taken anytime of the year, but they should be taken early enough to allow adequate time to implement the laboratory recommendations in time for the crop to be planted. For fall planting, soil samples should be taken in spring, and for spring planting, soil samples should be taken in fall.

How do I take soil samples?

1. Get soil sample information sheets and cartons.

2. Clean tools and containers (bucket, etc).

3. Take one composite sample from each uniform area.

4. Take 10 to 15 small cores or slices from the large uniform area.

5. Take core slices about 4” deep for lawns and about 6” deep for fields.

6. Mix the cores or slices together in a clean bucket and take a sample of about one pint to represent the area sampled.

7. Complete the sample information sheet and carton information.

8. Draw a map and keep a record of where you sampled and sample numbers.

9. Include the information sheet with a carton of soil “sample” and mail or take to appropriate testing laboratory.

**TIP**

Avoid unusual areas unless you want to get a sample of the unusual area only so that it can be treated (such as dead or yellow spots in lawns or fields).

Interpreting Soil Test Reports

Ø The report will provide the results of the laboratory analysis and suggest a fertilization program, lime application and possibly other treatments based on test results.

Ø Actual nutrients available are reported in parts per million and also in levels such as high, low, very low, very high, slightly acid, etc. to help the plant grower understand the report.

Ø The level of acidity or alkalinity is shown by the pH. A pH of 7.0 is neutral. A pH of 6.9 or less is acidic and 7.1 or above is alkaline.

Ø If more information or assistance is needed, the cooperative extension agent, agricultural education teacher or other knowledgeable people who work with soil test reports should be contacted.