Bugs Eating Green Bean Plants

Bean Leaf Beetle

• Bean leaf beetles are chewing bugs that attach themselves to the leaves of the green bean plants and eat pieces out of the leaves. Measuring 1/4 inch long, this beetle is yellowish-green in color and has four black spots on its back. Bean leaf beetles spend the winter in the foliage in wooded areas and emerge in early summer. Keep these green-bean-plant-eating bugs under control by removing dead leaves and foliage from the ground. If you think you may have a bean leaf beetle infestation, confirm the infestation by looking for beetles on your bean plants between 12:00 p.m. and 4:00 p.m., as this typically warm time of day is when the beetles feed.

Cutworms

• Cutworms are a group of night-flying moth caterpillars. These chewing bugs eat green bean plants by chewing off the stalks of young plants at ground level. Some varieties climb onto the plant and also eat the foliage and upper stems. Cutworms are identifiable by their defense mechanism: When disturbed, these pesky caterpillars roll up into a tight "C"-shaped ball. Keep cutworms under control by removing weeds from your crop fields and crop borders, as they make ideal laying grounds for cutworm eggs. If you think you may have a cutworm infestation, inspect your crops early in the morning when the damage is fresh, and you may even catch some cutworms still feeding.

Potato Aphid

• The potato aphid is a large sucking bug that feeds on the green bean plant's flowers. The potato aphid can be identified by its coloration of either pink or green. These aphids are 3mm long with fat bodies. The excrement, or honeydew, that aphids secrete results in a black, soot-like mold on the leaves.