Milo I. Harpstead, Ph.D., is certified as a Professional Soil Classifier with the American Registry of Certified Professionals in Agronomy, Crops, and Soils (ARCPACS) within the Society of American Agriculture. He is a former Professor of Soil Science at the University of Wisconsin-Stevens Point. Dr. Harpstead also has taught and supervised research for students in Nigeria, Malaysia, Germany, and Australia.
Thomas J. Sauer, Ph.D., spent three years as a Soil Physicist with the USDA Agricultural Research Service Biomass Center in Arkansas and is now a Soil Scientist for the national Soil Tilth Laboratory, Ames, Iowa, where he conducts research on soil management impacts related to agroecology and air quality.
William F. Bennett, Ph.D., has been involved in teaching Soils, Soil Fertility, and Crops for over 40 years. He is a former Director of Development for the College of Agricultural Science and national Resources at Texas Tech University in Lubbock. In addition to work as a Soil fertility Consultant, Dr. Bennett is currently involved in educational programs in the fertilizer industry, with emphasis on the Certified Crop Advisor Program.