Northwest and Allee Research and Demonstration Farm
Soil moisture samples were taken at 11 sites in northwest Iowa during the first few days of November, 2009. Moisture samples were pulled at 1-ft increments down to a 5-ft depth. Samples were weighed, oven dried, and reweighed at the Northwest Research Farm, Sutherland, IA.
Iowa State University
DeJong, Joel L., "Soil Moisture" (2010). Iowa State Research Farm Progress Reports. 422.