Pest Identification: Weevils
Most Common Types
There are about 60,000 species of weevil, which is a type of beetle. They are plant-feeders, often named for the food they consume. Wheat weevils eat grain, while boll weevils attack cotton buds or bolls.
What They Look Like
The most common weevils found in the home are wheat weevils. They are reddish-brown in color and small in size, about 3 to 5 millimeters in length. They have long snouts and mouthparts, and cannot fly. Wheat weevil larvae are also legless.
Where They Live
Wheat weevils are found across the globe wherever wheat, oats, rye, barley, rice, corn, or other types of grain are stored.
Where They Nest
A single female wheat weevil produces from 30 to 250 eggs. Each egg is laid inside a single grain kernel. When the larvae hatch they feed on the grain for 5 to 20 weeks. When they reach adulthood, the weevils pop out of the grain kernel to mate.
Steps to Prevent
Weevils are most often carried into the home via infested grain purchased at a store. When buying any type of unprocessed grain inspect the bags for small holes. Weevils can chew through paper and plastic packaging. Keep bags of grain in the freezer for at least one week to kill larvae. Buy grain in small quantities so it does not sit on the shelf for extended periods. Be sure to store grains in air-tight jars or sturdy plastic containers.
Are They Harmful?
Weevils cause untold damage to grain harvests worldwide and are difficult to detect. When they infest a storage facility, all grain within must be destroyed. However, if you find weevils in your pantry, they will not cause physical harm to pets or people. Discard infested food and make sure the weevils have not laid eggs in other supplies of stored grains.