Last week, we were asked when a grower should be concerned about adult corn rootworms feeding on the silks of their corn. The importance of beetle feeding on corn silks is variable and there is not a definitive treatment threshold. The variability is the result of the environmental conditions and the maturity of the corn in relation to surrounding fields. During the 1970s, Purdue University conducted a study to try to identify a treatment threshold for adult rootworm feeding. The resulting threshold was 5 to 15 adult rootworms per plant.
Iowa State University
Tollefson, Jon J. and Rice, Marlin E., "When should you be concerned about adult corn rootworm feeding on your corn?" (2007). Integrated Crop Management News. 1003.
The Iowa State University Digital Repository provides access to Integrated Crop Management News for historical purposes only. Users are hereby notified that the content may be inaccurate, out of date, incomplete and/or may not meet the needs and requirements of the user. Users should make their own assessment of the information and whether it is suitable for their intended purpose. For current information on integrated crop management from Iowa State University Extension and Outreach, please visit https://crops.extension.iastate.edu/.