Annual White Grub Control on a Golf Course Fairway in Lancaster Co., Nebraska, 1995

Abstract

Abstract This study was conducted in Lincoln, NE on a golf course fairway. The turf (50% Kentucky bluegrass and 50% perennial rye) was maintained at a mowing height of 11/16 inches. Thatch accumulation (finger compressed) in the plot area was 0.375 to 0.50 inches. Field conditions at the study site were: soil type, silty clay loam; soil organic matter, 3-5%; soil pH, 6.7; water pH, 7.0. Environmental conditions at the time of application were as follows: soil moisture 21%; air temperature 78°F; soil temperature 83°F; relative humidity 64%; wind direction and velocity 31° at 6 mph. Plots were 40 inches X 15 ft and the experimental design was a RCB with 4 replications. Insecticide applications were applied on 9 Aug 1995 using either a Cushman prototype subsurface applicator designed to place insecticide granular treatments at the soil-thatch interface (avg depth 0.5 inches), or a CO2 sprayer with an LF4 nozzle at 40 psi and delivering 3 gal/1000 ft2. Following applications, plots were irrigated with 0.25 inches of water. Post-treatment precipitation totaled 0.67 inches. Treatments were evaluated 28 DAT on 6 SEP by removing from each plot three, 8-inch diam turf-soil cores (1.05 ft2 total area) to a depth of 3 inches and counting the number of surviving grubs. Pretreatment counts indicated 10-20 SMC/ft2 with 18% eggs and 82% second instars in the test area.