Control of White Grubs in Turf Using Carbaryl Formulations, 1995

This test was conducted in turf-type tall fescue at the University of Kentucky Spindletop Farm, near Lexington. The turf was on a Maury silt loam soil (pH = 6.4) with negligible thatch. Plots (4 X 6 ft: 2 ft untreated borders) were arranged in a RCB with 4 replications. The turf was treated on 17 Aug, after egg hatch of JB and SMC. At that time, the population consisted mostly of 1 st and 2nd instars. Granular formulations were preweighed, mixed with dry sand, and applied evenly to the plots by gloved hand. Liquid applications were applied at a volume of 50 gal/acre using a low volume, CO2 sprayer equipped with 4 Spraying System 8004 Tee Jet nozzles that delivered 2109 g pressure per cm2. Each plot was syringed with about 1/8 inch of water within 5 min after application, and the whole site received about 3/4 inch of irrigation as soon as the last treatment was applied. Conditions at the time of treatment were 90°F with winds < 10 mph. The most recent precipitation before the treatment date was on 10 Aug, when 1.70 inches of rain fell. There was 0.44 and 0.17 inch of rain on the 18th and 19th of August, respectively; i.e., 1 and 2 DAT. Plots were sampled on 16 Sep. A motorized sod cutter was used to cut a 3 X 1.5 ft strip, about 3 inches deep, from the center of each plot. The sod was rolled back, broken apart, and all grubs were identified and counted.