Extension > Garden > Diagnose a problem > What insect is this? > Garden Pests > Caterpillars, maggots, grubs, and similar immature insects - 1/4 inch - 1/2 inch long > Colorado potato beetle
Colorado potato beetle
Leptinotarsa decemlineata

Jeff Hahn, University of Minnesota Extension

Jeff Hahn, University of Minnesota Extension
Description: Up to 3/8 inch long.
Where/When: Feeds on potato as well as eggplant, tomato, pepper, and related plants. The larva is active from June through September.
Significance: Chews leaves; potatoes can tolerate up to 30% defoliation when they are in a vegetative stage but can only tolerate ten percent defoliation when tubers are bulking up. Severe defoliation can reduce plant vigor, size and yield.
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