Submitted to: Soil Science Society of America Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: July 28, 2004
Publication Date: November 2, 2004
Citation: Starr, J.L., Teasdale, J.R., Sadeghi, A.M., Rowland, R.A. 2004. Impact of cover crop and weeds on soil water dynamics in corn [abstract]. Soil Science Society of America Annual Meeting. 2004 CDROM 3561. Technical Abstract: Weed competition for soil water and its resultant impact on corn growth has not been well documented. This research was conducted in continuous no-tillage corn to assess the impact of cover-crop residues (plus or minus hairy vetch) and weed competition (plus or minus) on water uptake rates and crop growth over two growing seasons. Treatment impacts were studied in 16 one-m2 subsampling areas (SSA) within replicated field plots during two droughty years. Soil water content at four soil depths was continuously monitored using multisensor capacitance probes located at the center of each SSA. Vegetative biomass of weeds and corn was obtained for each SSA just prior to the onset of plant senescence. Negative impact of weed growth on corn biomass was about three times greater under NT than under HV due to weed suppression under HV cover. Weeds had higher N, K, Ca, and Mg content but lower P content than corn, suggesting relative nutrient uptake was not always linked to water uptake. Water uptake rates following rainfall events were generally significantly different by depth and by weed competition.