Appearance and Size Facts
- Dark brown in color and are somewhat cylindrical in shape
- Prolonged head with a distinct thin snout extending downward from the head
- Well marked thorax.
- Size: Approximately 1/8-inch long
- Internal feeders and cannot fly
Behavior and Habitat of Granary Weevils
Granary weevils are internal feeders and they cannot fly. When disturbed, Granary weevils play dead by drawing their legs close to their body. They then lie still for several minutes before resuming movement.
The female uses her strong mandibles to chew a small hole in a grain kernel, where she deposits a single egg in the hole and seals it with a gelatinous fluid. In warm weather, the granary weevil can develop from egg to adult in about five weeks. Cold weather prolongs development.
Granary weevils are similar to Rice weevils and they are both often referred to as the Snout weevils. They penetrate and feed on the internal portions of whole grains during the larval stage. Granary weevils are usually found in grain storage facilities, food processing plants, and whole foods markets. They will also infest old pasta, table beans, acorns, chestnuts, birdseed, sunflower seeds, and ornamental corn.
Signs of Infestation of Granary Weevils
The Granary and Rice weevils are the most economically significant pests of stored grain. Damage to grain products will be severe, as the larvae develop inside the grain kernels. Wheat, corn, macaroni, oats, barley, sorghum, Kaffir seed, and buckwheat are just some of the grains and products these weevils destroy.
Tips for Prevention of Granary Weevils
Discard any infested foods, vacuum pantry shelves, cracks, and crevices and make sure to dispose of garbage and vacuum bags outside, away from the home, wipe shelves with white vinegar.