Control of Annual White Grubs in Kentucky Bluegrass, 1987

Seven insecticides were applied to 3- × 6-ft plots in a lawn in Lincoln, Nebr. (Lancaster County), on 10 Jul. Granular formulations were combined with 4.8 oz Milorganite, which served as a carrier, and were hand shaken over plots. Liquid formulations were applied with a C02 sprayer using a LF-4 nozzle at 28 psi and a spray rate of 4 gal/1000 sq ft. To ensure uniformity among plots, 4.8 oz of Milorganite also was applied to plots receiving liquid formulations and over untreated checks. The experiment was replicated 4 times using a randomized complete block design. Immediately following insecticide applications, the test area was irrigated with approximately 0.5 inches of water. An additional 1.0 inch of water was applied during the next 2 wk. No rainfall occurred during the posttreatment period. Product efficacy was evaluated 14 days after application (24 Jul) by removing 2 sections of sod, 1-sq-ft × 4 inches deep, from each plot and counting the number of surviving grubs.