Control of Wireworm on Sweet Potatoes, 1973

On Jun 4‘73 ‘California’ sweet potato sprouts were transplanted in 2 row plots (32 inch row spacing) 45 feet in length. Plant population on an acre basis was approximately 14,000 plants per acre. The soil was a Norfolk “A” loamy sand. The treatments were arranged in a randomized complete block design with 4 replications. All chemicals were applied as a broadcast treatment using a small Gandy push-type applicator. Preplant broadcast treatments were applied May 28‘73 and were incorporated 3-5 inches into the soil with a single discing. Soil temperature at the 4 inch depth at the time of preplant application was 22°C. Post plant treatments were applied over the foliage at root-swell on July 24. Yield data were taken from 2 sections of row, 35 feet in length. At harvest time 100 roots/treatment/replication were selected at random and examined for wireworm injury.