Control of Russian Wheat Aphid on Winter Wheat, 1989:

Twelve insecticides in a total of 15 formulations were evaluated as controls against the RWA in a heavily infested field near Davenport, Lincoln County, WA. Treatments were applied on 15 Nov with a CO2-powered backpack sprayer with a 9 ft boom calibrated to deliver 20 gal/acre at 30 psi. At treatment, all of the plants had from 2-5 tillers. Plots were 18 x 18 ft, each separated by an 18 ft buffer row, and replicated 4 times in a RCB design. These plots were located within a block of wheat seeded on 20 Sep (seeding rate: 98 lb/acre, 10 inch row spacing). At least 10 plants and over 50 total tillers were taken at random from each plot, placed into paper bags, and transported back to the lab in coolers. Aphids were recovered from samples using Berlese-Tulgren funnels. The number of plants and tillers for each sample was recorded. Aphid population densities for this evaluation are expressed as numbers of aphids per tiller. RWA represented 98% of the aphid species present; most of the remaining 5% were bird cherry-oat aphid. This proportion was not changed by the insecticide treatments.