Peters, John B. and Carrie Laboski. 2013. Sampling Soils for Testing. University of Wisconsin Cooperative Extension. Accessed at: <http://www.soils.wisc.edu/extension/pubs/A2100.pdf>
Sampling Soils for Testing out of the University of Wisconsin Extension, and written by John Peters and Carrie Laboski covers planning for nutrient management on your farm, and how important a role correct soil sampling techniques are to proper nutrient management. Selecting a sampling strategy and procedure for taking soil samples are discussed in some detail.