Colorado potato bug Leptinotarsa decemlineata
IDENTIFICATION — The larvae and the 1/2-in.-long adults chew large, ragged holes in leaves, flowers and fruit of potato, pepper, eggplant and tomatoes. Heavy infestations can kill plants. At this point in the season you’ll see the late-summer generations of the black and yellow striped adult beetle.
CONTROL — For a few beetles, handpick insects and drop them in soapy water. If you see several on a plant, spread a white drop cloth beneath it and gently tap the plant. Destroy adults and larvae that fall onto the drop cloth and also check the undersides of leaves for the yellow-orange egg masses and send them away in the trash. The Bt strain Bacillus thuringiensis var. tenebrionis and insecticides containing neem control adults and larvae when applied as soon as you spot them. And though it’s not too late to control them now, next year start looking for them in early spring on vulnerable plants.