Annual White Grub Control on a Golf Course Fairway Using Subsurface and Conventional Application Methods, 1994
Abstract This study was conducted in Lincoln, NE on a golf course fairway. The turf (100% Kentucky bluegrass) was maintained at a mowing height of 5/s inches. Thatch accumulation (finger compressed) in the plot area was 0.5 to 0.75 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. Soil moisture was maintained at approximately 17% by weight, throughout the study. Plots were 40 inches × 15 ft and the experimental design was a RCB with 3 replications. Insecticide treatments were applied on 23 Aug 1994 using either a Cushman prototype subsurface applicator designed to place insecticide granular treatments at the soil-thatch interface (avg depth 0.75 inches), or a Gandy 24H12 drop spreader. Following applications, plots were irrigated with 0.5 inches of water. Posttreatment precipitation totaled 0.42 inches. Treatments were evaluated 21 DAT on 13 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 10-40 SMC/ft2 with 80-90% in the third instar stage in the test area.