First-Generation European Corn Borer Control with Ground, Aerial, and Center Pivot Applications, 1987

Insecticide trials were established at 3 locations in South Dakota. The experimental design for 2 ground trials was a randomized complete block with 4 replications at Redfield and 3 replications at Beresford. Individual plots were single-row treatments 30 m long for the ground trials. A center pivot trial was conducted at Redfield and an aerial study was established at Armour. Ten plants with shot-hole injury midrib feeding, or both, were evaluated per replicate from each treatment for the ground trial locations. Damage was measured on the basis of one cavity equaling 2.5 cm of tunneling. Four sites were chosen randomly from within the aerial and center pivot treatments, and 10 plants/site were evaluated for damage. Experimental and registered products were tested at Redfield and Beresford. Pioneer 3475 was planted at a seeding rate of 60,540 seeds/ha on 22 Apr at Beresford. Granular materials were applied with a pneumatic applicator powered by a 3.5-horsepower engine mounted on a high-clearance ground applicator. Insecticide was metered by Noble metering units that were chain driven by a 12 V DC motor. Insecticide was banded (20 cm) over the whorl. Liquid insecticides were applied with a backpack sprayer. One 1.5 LE Even Flat Nozzle/row, pressurized at 15 psi was used to apply 19.5 gal/acre at 3.5 mph. All insecticides were applied at Beresford on 26 Jun. Stalks were split on 3 Aug and damage measured. Pioneer 3737 was planted at a seeding rate of 63,500/ha on 1 May at Redfield. Insecticides were applied on 29 Jun at Redfield. Plants were evaluated for injury on 4 Aug. Pioneer 3901 was planted at a seeding rate of 73,388/ha on 1 May at the center pivot trial in Redfield. Insecticides were injected with a Northern chemigation unit into a Valley electric drive center pivot irrigation system from 26 to 27 Jun. Plants were evaluated for damage on 4 Aug. Two irrigation rates of 0.53 and 2.5 cm water/day were used. The aerial trial was conducted at Armour. Dekalb 1100 was planted on 28 Apr at a rate of 63,010 seeds/ha. Insecticides were applied on 26 Jun with a fixed-wing aircraft in single swath treatments 13.7 × 402 m long. Stalks were split on 3 Aug and damage assessed.