Control of Alfalfa Insects in Iowa (Middle Season), 1986

Experimental plots measuring 10 X 12 m were established in a 3-year-old stand near the city limits of Ames, IO. Eight treatments were replicated 4 times in a randomized complete-block design. Insecticide treatments were applied on 2 Jul ‘86 with a Suzuki LT-125 4-wheel all-terrain cycle equipped with a 6.1-m boom. The C02-charged boom was ca. 61 cm from the foliage and fitted with twelve brass 8003 flat-fan nozzles. Ground speed was 6.28 km/h, delivering 112.2 liters of final solution per hectare. Plants were in stage 2 (late vegetative) and ca. 36 cm tall. Weather conditions at application time were sunny, winds 0-3 km/h, temperature 21-24 degrees C, and ca. 60% RH. A standard 38-cm sweep net was used to take 10 pendulum sweeps in each plot just before treatment and 1, 5, and 10 days posttreatment. No phytotoxicity was observed in any plot.