Issue No. 10, Article 1/May 29, 2009
Significant Black Cutworm Injury Reported in Ohio: Don't Forget to Scout Corn Fields
A recent report from Ron Hammond, extension entomologist at Ohio State University, indicates that some corn fields in Ohio have significant densities of black cutworms, exceeding the economic threshold in several instances. Producers should anticipate some cutting of plants this spring because of the wet weather, excessive weed growth in many fields, delayed planting, and intense captures of black cutworm moths. When dry weather returns and planting resumes in earnest, producers will increasingly find themselves squeezed for time and may neglect to scout corn fields and miss the early signs of black cutworm leaf feeding that signal potential cutting. This could be a costly mistake, especially as replanting decisions for corn at this point result in stiff yield penalties.
Black cutworm leaf feeding injury.
If you discover that 1% of your corn seedlings have leaf feeding, this injury signals that future cutting is possible at economic levels (3% to 5% cutting). Don't assume that Bt corn, insecticidal seed treatments, or the use of a soil insecticide at planting will eliminate the threat of black cutworm damage. Significant infestations of this pest present a challenge for many management options. For a complete review of black cutworm biology, life cycle information, and management strategies, take a look at this University of Illinois Extension fact sheet.
If you are experiencing black cutworm cutting in your area of the state, please let me know so I can share your observations with our readers.--Mike Gray