Nutrient Testing

Taking samples (soil, manure, forage, or water) is an important part of nutrient management. This information can help you:
  • Determine agronomic application rate
  • Budget fertilizer and manure use more effectively
  • Monitor and adjust yields and feed quality
  • Avoid feed toxicity and head health issues
  • Self monitor and correct pollution sources

Click HERE for more information on the legislative requirements (WAC 16-611) of nutrient testing and recordkeeping.

Click on the following area of interest to find out more about proper sampling techniques, handling procedures, and nutrient analysis information for:

You are required to take the following samples for nutrient management:

  • Comprehensive soil test every three years for each field or management unit (ground of fields) (click HERE to see what dairy operations are required to test for)
  • Annual fall nitrate test for each field or management unit (ground of fields)
  • Annual comprehensive manure test and in-field N test for rest. The number of manure tests taken per year will vary by operation and management. On average, it is recommended that you have a representative test for each season of crop application.

The following tests are voluntary, but recommended:

  • Forage tests. Taking a forage sample will help you determine the levels of nutrient such as N and K, which can both have detrimental effects on heard health if in excess.
  • Irrigation water test. Irrigation water can have increased levels of N in the form of nitrate in certain geographic areas. Knowing how much N is in your irrigation water is important for N budgeting because if levels are high, fertilizer rates may need be adjusted to account for the extra N application. 
  • Surface water testing. If you are in a high risk area, or think you may have leaking tanks, tiles, fields, etc., you can test your own surface waters. This is a good self monitoring practice and a way you can determine if you need to make changes to your farm or practices, or protect yourself from your neighbors issues.