Granary and rice weevils can be found living in grain stores such as bins, silos and elevators. Both types of weevil can be found infesting wheat, corn, barley and rice supplies. Considered a pantry pest, weevils may even infest pasta, bean, nut and cereal containers and storage bins. While infestation is pretty rare in homes, weevils are occasionally found when outside sources are brought inside. This includes bird seed, nuts, and decorative corn.

Granary and rice weevils are detrimental to stored, whole grain supplies. Granary and rice weevils are internal feeders. As the name suggests, internal feeders feed within the kernels of whole grains. Not only do they feed on the grains themselves, but female weevils lay eggs in the kernels of whole grains as well.

A female weevil will bore holes into grain kernels where she will then lay a single egg. Once deposited, she will move on to the next kernel and lay another egg. This process continues until she deposits around 300 to 400 eggs, though only about 50% of these will actually hatch. Larvae will emerge out of the eggs and will feed within the kernel until it is an adult. Eventually, the adult weevil will chew itself out of the kernel, leaving a round exit hole. Because the weevil grows within the kernel, its size depends on the size of the kernel. The larger the kernel, the larger the weevil.

If disturbed, granary and rice weevils will “play dead” as a defense mechanism. A weevil will bring its legs close to its body and lie still until the threat goes away.

Weevils are typically brought into homes through an outside source, more than likely some kind of packaged food. They may have originated from a warehouse, processing plant, or delivery vehicle. However, it is possible for weevils to enter your home from outdoors. If not contained, weevils can reproduce and spread to other suitable food products.

You might have a weevil infestation if you notice small holes in any whole grains you have stored or see any live, adult weevils in stored food.

It can be very difficult to to get rid of weevils as they are very hard to detect. To prevent an infestation from happening in the first place, you should practice and maintain cleanliness. This means cleaning food containers and storage once they become empty and disposing of infested food as soon as possible. Storing food in plastic or glass containers with tight lids is also a good idea. If you suspect your food may be infested, weevils can be killed by freezing the food at a very low temperature or heating the food to a very high temperature.