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Standardized tests MAPP accurate manure analysis

April 8, 2020  by Manure Manager

For farmers in Arkansas, California, Iowa, North Dakota, Minnesota, many other states or Canada, the Minnesota Department of Agriculture (MDA) could play a role in your cropping manure application program.

For the past 25 years, the MDA has offered North America’s only Manure Analysis Proficiency Program (MAPP) for laboratories that test manure. The primary goal of the program is to ensure that farmers receive accurate manure test results.

Part of the challenge of accurately testing manure comes from the varieties of manure produced: different consistencies, species of animals, and form the sample is in when received by the lab.

As farmers began to recognize the value of properly-applied manure, a need developed for reliable results. With differences in procedures, lab technicians and equipment, labs needed standardization to get repeatable results.


Public and private labs enroll in this program annually. Labs receive unknown samples of manure in May and again in July. The manure is analyzed and results are returned to the MDA to check accuracy. Then, the participating labs receive graphical and tabular reports for each lab showing how their results compare with the results submitted by the other participating labs.

Labs pay $400 annually to participate in MAPP. In addition to proficiency, some labs elect to go one step further and become certified for manure testing through the Manure Testing Lab Certification program. The MDA certifies labs with acceptable accuracy in total nitrogen and total phosphorus for an additional $100.

Farmers are invited to contact participating labs to learn what tests are conducted and the best method for collecting and shipping samples. Some labs offer sample containers, and it’s important that farmers ship the samples as soon as they are collected.

For more information and a list of participating labs, visit the Minnesota Department of Agriculture’s 2020 Certified Manure Testing Laboratories page.


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