Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: July 15, 1998
Publication Date: N/A
Technical Abstract: Limited water holding capacity, coupled with a root-restricting horizon, presents a challenge for producing crops on the Coastal Plain. Irrigation and varying tillage systems have been used to optimize crop production. To determine the impact of irrigation and tillage on the leachability of pesticides, a study was undertaken to assess the lateral movement of two herbicides. Replicated corn plots were established under a center pivot irrigation system. The plots were divided into two tillage treatments (subsoiled and non-subsoiled) and two water management schedules (irrigated and non-irrigated). Incremental soil cores to a depth of 122 cm were collected 2, 4, 8, and 16 weeks after herbicide application. Herbicides were extracted utilizing solid-phase extraction columns and determined by gas chromatography. Concentrations of both herbicides generally were highest in the top 15 cm of the soil profile regardless of tillage or irrigation treatment. The interaction between irrigation and tillage will be detailed and losses will be presented.