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Black cutworms (Agrotis ipsilon) are occasional pests of many vegetables and can cause considerable stand loss. Black cutworms are active on many vegetable crops from transplanting until stems toughen or reach more than 1⁄2 inch in diameter. They are more likely to be found in fields with a history of cutworm damage, those planted under reduced or no-tillage practices, or those with poor drainage. Excessive fall or spring weed growth and the amount of surface residue influence the potential for cutworm infestations. The cutworms are light gray to nearly black with a faint, narrow, stripe down the middle of the back. The skin appears “greasy” and to contain tiny granules. Larvae can reach 13⁄4 inches in length when full-grown. They will be coiled in a compact “C” when uncovered. Cutworms are active at night, feeding first on leaves when small and later cutting plants as they grow. Infestations usually begin on early-season weed growth prior to field preparation.

Black cutworm

(Photo: UK Vegetable IPM Team, University of Kentucky)

Management: 

• Early land preparation two or more weeks before transplanting and good weed control will help to reduce cutowrm problems. 
• It is important to watch the field closesly for seedlings with small holes in the leaves or cut plants. Early detection means an insecticide application can be made before serioius damage occurs.

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