1. Topsoil Thickness Effects on Phosphorus and Potassium Dynamics on Claypan Soils

Due to variable depth to claypan (DTC) across landscapes, nutrient supply from subsoils, and crop removal, precise P and K fertilizer management on claypan soil fields can be difficult. Therefore, a study was performed to determine if DTC derived from soil apparent electrical conductivity (ECa) could be used to improve P and K management for corn (Zea mays L.) and soybean (Glycine max [L.]). Research was conducted on a claypan soil at the University of Missouri’s... L. Conway, M. Yost, N. Kitchen, N. Kitchen, K. Sudduth