This small-plot trial evaluated efficacy of granular insecticides in a commercial production field near Beardsley, Minn. Plots of 1 row (30-inch spacing) by 50 ft were arranged in a randomized complete block design with 4 replicates. Granular insecticides were applied to whorl stage corn 8 Jul when temperatures were 70-75°F and there were light variable winds. A one-row, electrically driven Gandy granular insecticide applicator was used to apply all treatments. Insecticide performance was evaluated 9 Aug by dissecting 10 infested plants/plot and counting the tunnels.

Performance of liquid insecticides applied to foliage was evaluated in small plot trials on pretassel corn near Crookston, Minn. Plots of 2 rows (5 ft) by 50 ft were established 10 Jul in a commercial field planted 4 May. Treatments were arranged in a randomized complete block design with 4 replicates. Insecticides were applied with a CO2-powered backpack sprayer delivering 17 gal water/acre through Zytel LF-3-80 nozzles at 40 psi. Light winds (<2 mph) and warm temperatures (89°F) prevailed during application, but IV2 inches of rain began to fall within 6 h after application. Insecticide performance was evaluated 19 Aug by dissecting 10 plants/plot and counting all damage sites (tunnels in stalk, ear shank, and ear).

Performance of granular and liquid insecticides against first-generation ECB larvae was evaluated in a small-plot trial near Angus, Polk County, Minn. Plots of 2 rows (30-inch row width) and 30 ft, were established in a commercial production field. Treatments were arranged in a randomized complete block design with four replicates. Ground application of insecticides was made 17 Jul under light winds (<4 mph) and temperatures ranging from 70 to 80°F. Liquid formulations were broadcast with a CO2-powered backpack sprayer delivering 17 gal/acre at 40 psi through Zytel LF-3-80 nozzles. Granular formulations, premeasured for each plot, were manually applied with a shaker jar. Efficacy was evaluated 26 Aug by dissecting 10 plant/plot and counting the tunnels.

Performance of granular insecticides against ECB larvae was evaluated in a small-plot trial near Red Wing, Minn. Plots of 1 row (30-inch row spacing) by 50 ft, were located within a commercial production field that was planted on 2 May. Larvae varied from first to fourth instars with the majority in the third instar. Insecticide treatments were arranged in a randomized complete block design with 4 replicates. Granular insecticides were applied with a one-row, electrically driven, Gandy applicator that was manually pushed through the plots. A liquid standard, Pounce 3.2 EC, was applied in 17 gal water/acre at 40 psi through 8002 nozzles on a CO2-powered backpack sprayer. The treatments were applied 22 Jun when temperatures ranged from 85 to 90°F and winds were 10-15 mph. Efficacy was evaluated on 10 Aug by dissecting 10 infested plants/plot and counting the tunnels.