Weevils lay eggs on grain kernels; after they hatch, the larvae burrow into the grain. Large cracked corn grains can harbor these pests before you even become aware of an infestation. True granary and rice weevils typically only infest large or whole grains like cracked corn, so your flour and other ground grains are usually safe. You can remove the weevils before they emerge by putting your corn in the freezer, which freezes the pests and ensures it's safe to eat and that your pantry remains weevil-free.
Package the cracked corn in small glass or heavy plastic jars with tight-fitting lids. Use containers that are only large enough to hold enough cracked corn that you can use it up within 2 to 4 months.
Place the jars in a 0 degree Fahrenheit freezer. Freeze the corn for 4 days, which will kill any weevil eggs in the corn.
Remove the cracked corn from the freezer and store it in a clean pantry. Keep the lid on the container at all times. If you will not use the corn within 4 months, continue to store it in the refrigerator or freezer to guard against reinfestation.
Wipe down pantry shelves and vacuum out the pantry regularly so no spilled grains or adult insects are present, which could lead to a weevil reinfestation. Crumbs, spilled grains and food particles, opened packages of food, and pet foods can attract weevils, so keep the pantry and food storage areas clean at all times.
Store all grains, not just cracked corn, in glass or heavy plastic containers. Weevils can chew through paper, cardboard and plastic bags, so they do not offer protection.
Small cloth bags of black pepper can help repel weevils. Place the bags around stored food and grain products to discourage the pests.
Do not use insecticides to control weevils in or near food items.
Dispose of any food that has visible larvae or adult insects.