Weevils are actually beetles that range in size from about 3 mm to over 10 mm in length. They feed on plants in the larval stage and as adults as well, being very destructive to crops. They also attack stored grains and seeds, their damage level being often very expensive. They also invade homes, often in the fall, shelter there during the winter and leave in the spring. The grain weevils hurt human beings on a larger magnitude by compromising food supplies. What they lack in stinging or biting, they make up for in causing destruction on a potentially massive scale concerning food supplies.
Wheat weevils or grain weevils are a pest of wheat, oats, rye, barley, rice and corn. They cause an unknown amount of damage worldwide because keeping track of so much information is difficult, especially in places where the grain harvests are not measured. They are hard to detect and usually all of the grain in an infested storage facility must be destroyed. Many methods attempt to get rid of the wheat weevil, such as pesticides, different methods of masking the odor of the grain with unpleasant scents, and introducing other organisms that are predators of the weevils.
Sanitation and inspection are the keys to prevent the infestation. Grains should be stored in preferably metallic (cardboard, even fortified, is easily drilled through) containers with tight lids in a refrigerator or a freezer, and should be purchased in small quantities. If any suspicion has arisen, carefully examine the grains for adult insects or holes in the grain kernels. Another method is to immerse them in water. If they float to the surface, it is a good indication of infestation. Even if identified early, disposal may be the only effective solution.
Females lay their eggs inside kernels, and the larvae can stay inside it for one to five months after hatching, just feeding on the inside of the kernel. Upon reaching adulthood, the weevil emerges from the kernel to mate and look for new grains to invade. Rice weevils, bean weevils and other stored food weevils feed inside food packages. They can remain hidden in the pantry for a long time. Homeowners might spot adult weevils wandering on the shelves or floor of the pantry.
Prevent infestation with grain weevils
You can prevent such a thing from happening by disposing of old bags with grains, forgotten in the back of your cupboard. Buy grains in small quantities and use them within a reasonable period of time, as by leaving them unattended for long, weevils might find their way to them. always store wheat, rice, oats or other cereal in tightly sealed glass, metal, or sturdy plastic containers, as weevils can’t make their way through such materials. They can, however, go through paper bags, so try to avoid using them. In order to kill any eggs, you can freeze the grains for at least a week, or permanently keep them in the freezer. Keep in mind to regularly clean your pantry shelves, and make sure you cover any cracks or crevices that may appear in this area.
In order to repel weevils through smell, you can also use black pepper, bay leaf, clove, rosemary, or garlic cloves, as by placing them inside the pantry, you will keep the weevils away. You can also wipe your shelves with white vinegar, as the smell of it will also deter weevils. Make sure you keep your kitchen and whole house thoroughly clean, vacuum regularly and dispose of garbage in order to maintain a hygienic environment that does not allow weevils to form a shelter inside your home.
Reduce the risk of bringing weevils in your house
- Try buying cereals in clear packaging so that you can still inspect the content of the food you are buying;
- Avoid buying foods with damaged packaging, as they might already be infected;
- Seal possible entry points in your pantry, such as weather stripping around doors and windows, missing areas of caulk around doors and windows, or torn screens in vents, doors and windows;
- Freeze grains you suspect are already infested with eggs, as this method will kill the larvae; should you place the grains in water (this works best with rice) you will notice that the flowing ones are pierced and inside that hole, weevil eggs can be found;
- After freezing them, transfer your grains in metal, glass or plastic containers, as weevils can’t eat through such materials;
- Keep your pantry clean, as Weevils may be attracted to your home if there are bits of food lying around, such as flour dust, spilled cereal, or fallen grains of rice.
- Make sure you do not keep food in your pantry for too long; buy grains in smaller amounts and eat them in a decent time frame;
- Use herbs such as bay leaf, clove, rosemary, black pepper corns, and garlic cloves to keep away weevils; you can also add a few bay leaves inside each cereal container;
- Make sure you wash contaminated containers before reusing them;
- Clean under your kitchen appliances, as weevils may travel out to explore new areas of your kitchen if they’re attracted to any other food sources;
- Replace shelf paper before returning any type of food to the pantry, as weevils can hide underneath it; you can also wipe the area with eucalyptus oil or ti-tree oil to discourage weevils from resurfacing, as they do not appreciate these fragrances.
Should you be dealing with a serious grain weevil infestation, and the prevention methods have not worked, try using the tips on “How to get rid of Grain Weevils” from our relevant article.