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Soil Sampling and Testing

Soil testing is the best guide to the wise and efficient use of fertilizers and animal manure. The first step in soil testing is the collection of a representative sample. Soil properties vary a lot in a field. The soil sample must accurately represent the whole field where manure or other fertilizers are going to be applied. A minimum of 15-20 sub-samples is needed to make a composite sample for a field. For details of soil sampling see: How to Get a Good Soil Sample.

Sample bags, soil probe and other assistance's are available at your County Extension Office.


Soil samples should be submitted through your county extension office or directly to OSU Soil, Water and Forage Analytical Laboratory in Stillwater. You will find all the information you need about soil testing at our lab web site.

Manure Sampling and Testing

It is strongly recommended that the nutrient content of manure is determined by laboratory analysis annually or when manure handling procedure changes. The analysis report should at least include information of dry matter percentage, soluble salts or electrical conductivity, total N, ammonium N, total phosphorus and potassium.


The key to an accurate manure analysis starts from obtaining a representative sample by using proper sampling techniques. A considerable amount of nitrogen can be lost if a sample is not correctly taken, handled, and preserved. Depending on the solid percentage, manure can be classified into solid, semi-solid, slurry and liquid categories. Each type of manure requires different sample collection and land application technique. See Sampling Animal Manure for additional information.

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