Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: October 26, 1997
Publication Date: N/A
Technical Abstract: Drought reduces yield of summer crops and thus the amount of N removed from a field in the harvested portion. Winter cover crops can be used to trap residual N. Our objective was to determine site-specific effects of soil variation on the growth of a wheat (Triticum aestivum L.) cover crop following corn (Zea maize L.) that had low yield due to drought. In 1993, corn grain yield ranged from 1300 to 3300 kg/ha across 10 locations (representing six soil types) in an 8-ha field. Nitrogen removal from the field in the grain ranged from 14 to 41 kg/ha at these locations. Wheat biomass the following May ranged from 2032 to 7914 kg/ha. Nitrogen in the wheat ranged from 19.1 to 52.2 kg/ha. The data suggest that winter wheat scavenging of N is considerably variable both within soil types and across soil types. This variation may complicate optimizing N fertilization strategies for subsequent cash crops.