Biology of western bean cutworm in Michigan drybeans

Biology of Western Bean Cutworm in Michigan Dry Beans 2010

Western Bean Cutworm (WBC) is a new pest of dry beans and corn in Michigan. Moths were first detected in Michigan in 2006. My objective is to study WBC biology and behavior in dry beans in Michigan. WBC moths were trapped weekly throughout the summer of 2010 to monitor flight patterns, peaks, and shifts between crops. Peak flight was centered on the week of 24 July. Overnight observations were also made to see when moths were most active. Of 31 total moths caught overnight, 90% were caught between 1:00 am and 4:00 am. Bucket and milk jug traps were also compared at thirteen sites to look for differences in trap catch. A controlled study on dry beans determined larval distribution 1, 3, 5, 7, 14, 21, and 28 days after egg hatch (DAH). 1 to 3 DAH, larvae were found in the blossoms but were difficult to find later on. Based on overnight hourly observations, larvae were more active in the early morning and stayed on the ground when they were not feeding. Data from these studies will be used to better understand WBC in the Great Lakes Region and ideally develop more applicable methods of control.