Phenology of striped cucumber beetle (Acalymma vittatum), squash bug (Anasa tristis) and squash vine borer (Melittia cucurbitae) on muskmelon and butternut squash in Iowa

Squash vine borer (Melittia cucurbitae), squash bug (Anasa tristis), and striped cucumber beetle (Acalymma vittatum) cause substantial economic losses on several cucurbit crops. Timing of insecticide sprays, deployment of row covers, and other management practices are likely to be more effective if they correspond to the timing of arrival of these pests. To aid in development of degree-day models for cucumber beetle and squash bug, a flat of 2-week-old squash seedlings (cv. Blue Hubbard) was placed weekly in 10 randomly selected locations at the Iowa State University Horticulture Research Farm near Gilbert, IA, during April-June 2010. Flats were monitored three times weekly between 10 and 1 pm and target pest insects were counted. On June 11, the Blue Hubbard flats were removed and replaced by transplants of butternut squash (cv. Betternut) and muskmelon (cv. Strike) in two adjacent 50-ft-long rows (phenology plot). In this plot, ten randomly selected plants of each cultivar were inspected weekly for striped cucumber beetles and squash bugs; numbers of eggs, immatures, and adults were recorded. Monitoring for squash vine borer activity began on June 14, when two Hartstack traps were placed 100 ft apart in the phenology plot. These traps were checked weekly throughout the growing season. This project is part of acollaboration with Pennsylvania State University and University of Kentucky.