Fall Control of White Grubs with Insecticides on a Long Island Golf Course, 1986

Abstract

Abstract Nine insecticides were applied to a rough at the Huntington Country Club, Long Island, NY on 3 Sep for control of a mixed population of Japanese beetle, Oriental beetle, and northerr masked chafer grubs. The rough consisted of Kentucky bluegrass (30%), annual bluegrass (35%), bentgrass (20%), and broadleaf weeds (15%). Thatch wa;. minimal within the test plot (<.25 in.). The experimental design was RCB with 4 replications. Individual plots were 10 ft by 10 ft. Granular materials were applied with a precalibrated Gandy 2.5 spreader. Liquid materials were premeasured in the laboratory and applied with 11.4 liters (3 gal) of water through a watering can. All liquid applications were made in 2 directions within each plot. At treatment time the following environmental conditions existed: aii temp, 64°F; soil temp (3 inch), 67°F; soil pH, 5.22; water pH, 6.28; soil moisture, 15%. Approximately 0.2 inch of rain fell during and after insecticide application, and ca. 0.5 inch of water was applied through sprinklers the day of application. Posttreatment counts were taken 60 days later (23 Oct) by cutting a 1 ft by 10 ft strip (2.25 inches deep) lengthwise through each plot with a mechanical sod cutter and examining the sod and underlying soil for grubs. Three 1-ft2 samples of sod were examined in each plot and the no. of surviving grubs were counted. Species identification were made in the field. At this time Japanese beetles were predominantly third instars, with some second instars; Oriental beetle and northern masked chafer grubs were all third instars.