Insects

Root Weevils

Root Weevils
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Many species of root weevils cause trouble. The black vine weevil feasts on plants such as yew, rhododendrons, members of the rose family, and small fruits; the strawberry root weevil attacks a wide variety of plants, ranging from strawberries to arborvitae. The vegetable weevil (shown) feeds on carrots, tomatoes, spinach, and other plants.
Adults of all species are nocturnal, leaf-chewing, flightless beetles; they're about 1/3 inch long, with the typical long, curved weevil snout. When disturbed, they fall to the ground and play dead. The root-eating larvae are C-shaped, legless grubs with whitish or pinkish bodies and brown heads.

Target: Many plants. Particularly the rose family and small fruits.

Damage: Square or crescent-shaped notches are chewed in leaf edges (adults); plants wilt or die when roots are eaten (larvae).

Life cycle: The pests usually overwinter in the soil as grubs. After feeding heavily on roots, they pupate in late spring. Adults soon emerge and feed at night for several weeks; then each female lays hundreds of eggs on host plants or on the soil. Grubs burrow into the ground and feed sparingly on roots throughout summer. The adults of many species feed on foliage until fall. There’s usually one generation a year.

Notes: Gather burlap into 4 inch wide accordion folds; then hold the material so the folds run horizontally and wrap it tightly around the base of any woody plant with leaves showing feeding notches. When the weevils crawl down, they’ll nestle in the folds. Crush your catch daily. If you plan to use chemicals, it’s helpful to identify the particular weevil, since not all products control every species.