Control of Bluegrass Billbug Larvae on a Kentucky Bluegrass Lawn in Saunders Co., Nb, 1993

Abstract

Abstract Conven tional insecticides and entomopathogenic nematodes were evaluated for control of bluegrass billbug larvae on a Kentucky bluegrass lawn at the University of Nebraska Agricultural Research and Development Center near Mead, NB. The turf (100% Kentucky bluegrass) was maintained at a mowing height of 1.5 inches and thatch accumulation in the plot area was 0.75 inches (finger compressed, 0.50 inches). Field conditions at the time of application were: soil type, silty clay loam; soil organic matter, 3-5%; soil pH, 6.2-6.6; water pH, 7.0; soil moisture, near field capacity. Plots were 8 × 8 ft and the experimental design was a RCB with three replications. Insecticide treatments were applied 7 Jul. Granular insecticide treatments were applied with a precalibrated Gandy 24H12 spreader. Liquid insecticides and nematodes were applied using a CO2 sprayer with a LF-4 tip at 24 psi and delivering 4 gal finished spray/1000 ft2. The test area was irrigated with approximately 0.5 inches of water immediately following applications. A total of 3.88 inches of rain fell during the post-treatment period. Product efficacy was evaluated 21 Jul (14 DAT) by removing six 8-inch diam turf-soil cores (2.1 ft2 total area) to a depth of 3 inches and counting the surviving larvae.