White Grub Control, 1988

The experiment was conducted on a golf course fairway in Moraga, Calif. The stand was predominantly perennial ryegrass with some Poa annua var reptans (Hauskn.) Timm. Experimental design was a randomized complete block with 4 replicates. Plot size was 5 by 20 ft2. Granular formulations were shaken manually from a glass jar over the plots. Liquids were applied with a CO2-pressurized sprayer with a hollow-cone nozzle at 32 psi and 5.25 gal/1,000 ft2. Immediately after application, treatments were watered in with one-half inch water. Normal cultural practices were followed. Irrigation averaged 1 inch/wk. Water was pH 6.0. Thatch averaged one-half inch. Pretreatment grub density was determined 20 Sept by cutting 4 1-ft by 1-ft by 3-inch randomly selected sections in the sod in each plot and counting the grubs. Insecticide treatments were applied the same day. Posttreatment grub density was determined in the same manner 19 Oct, except that 5 sections in each plot were used for grub counts.