Fall or Late Winter Applications of Preemergence Herbicides Rarely Provide Season-long Control of Crabgrass (Digitaria spp) in Nebraska

Fall and late winter applications of preemergence herbicides (PREs) for crabgrass control have been evaluated in Illinois (Fermanian and Haley, 1994), Pennsylvania (Reicher et al., 2011), Indiana (Reicher et al., 2011; Reicher and Throssell, 1993), and Maryland (Dernoeden, 1993). The authors generally concluded that fall and late winter applications provide season-long control with higher application rates in areas with low/moderate crabgrass pressure. Many of these studies used older formulations of current active ingredients. None of these studies were located in the northwest edge of the transition zone where cool-season grasses dominate because of winter survival, but summer temperature extremes can thin even irrigated cool-season stands. Our objective was to determine if fall or late winter applications of PREs can provide season-long control of crabgrass in Nebraska.