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Angoumois Grain Moth

Article author: John Jackman
Most recently reviewed by: Pat Porter (2018)

Common Name(s): Angoumois Grain Moth, Grain moth

Description

Angoumois grain moths are occasionally found as pantry pests in homes, but they can be serious pests in commercial grain storage. Adult moths are a buff, tan or golden color and about 1/3 inch long. The wing span is 1/2 inch, rear edges of wings are fringed. Larvae are white with a yellowish to brown head and dark reddish-brown mouthparts. Larvae bore into kernels of cereal grains, pupate and emerge through a hole cut on the outer surface of the kernel.

Origin and Distribution

Grain storage, warehouses, bins, and pantries. Larvae feed on many types of whole grains. They prefer damp grain over dry grain.

Habitat & Hosts

They feed on stored grain, especially whole corn. The larvae require whole kernels or caked material for development. They bore into the kernel, pupate and emerge through a hole cut on the outer surface of the kernel. They are active at low temperatures and prefer barley, rye, corn, oats, rice and various seeds.

Life Cycle

Angoumois grain moth has a complete life cycle; egg, larva, pupa and adult, and it takes about about 5 weeks to complete development.  Adults can fly and are attracted to lights.

Management

If you live in the State of Texas, contact your local county agent or entomologist for management information. If you live outside of Texas, contact your local extension for management options.

In commercial/agricultural grain storage, control is complicated and requires the fundamental pest management steps of bin sanitation, grain leveling, aeration, monitoring etc. These things are beyond this fact sheet.

In homes and restaurants, control is simpler.

Nonchemical control.

The first step in controlling pantry pests is to find and eliminate infested items. Often all that is needed to solve the problem is to remove an infested package of flour, macaroni, or cake mix. But finding the source of an infestation is not always easy. Infested packages are usually the oldest, most difficult to reach foods in the pantry. Even unopened containers may be infested; some pests can easily penetrate plastic, waxed paper, and cardboard containers. Before buying an item in the store, check that the bag or container is well sealed and undamaged.

Good sanitation is important. Infestations often start in pet foods, spilled grains, or other foods. Clean up spilled food promptly. Discard old packages of grain and pasta. Vacuum and clean pantry areas periodically to remove spilled foods. Remove and clean underneath shelf paper. Caulk around pantry edges and in cracks and crevices to reduce areas where spilled food may collect.

Most pantry pest problems can be prevented by using all dried food within 2 to 4 months of purchase. Spices and other products kept for longer periods should be sealed in airtight containers.

Pet food can be a special problem.  The most commonly infested pantry items are birdseed and dog and cat foods. Store pet foods in well-sealed plastic buckets or storage containers and use them promptly. Clean the containers thoroughly before refilling them with food.

Occasionally, mice or other rodents can cause a persistent beetle infestation. Hoarded seed and grain in abandoned rodent nests can support a small population of pests. Old rodent bait that contains grain also can harbor insects. When controlling rodents, prevent insect problems by placing the bait where it can be retrieved and discarded after the rodents are controlled.

Heat or cold treatments can eliminate pests in some food items such as pet food, bulk grains and beans, and home-grown dried beans or peas. Put the product in the oven at 130 degrees F for 1 hour, or in the freezer for 7 to 14 days. To prevent an infestation, store foods that may attract pantry pests in the refrigerator or freezer.

Chemical control

On rare occasions, insecticides may be needed to control difficult infestations. Insecticides can reach inaccessible areas that cannot be easily cleaned; they can also help reduce heavy pest infestations more quickly.

Insecticide sprays may be applied to crevices and void areas around cupboards, drawers, and pantries. Before spraying, remove all food products, utensils, and containers from the treatment area. Allow the spray to dry before placing clean shelf paper on the shelves and returning food, utensils, or containers to the pantry.

Insecticide products that are labeled for use in food- storage areas generally contain ingredients that are short-lived and relatively safe to use in the home. Active ingredients of these products include pyrethrins, resmethrin, allethrin, and tetramethrin.

For areas where long-term residual control is de- sired, look for products containing synthetic pyrethroids, such as permethrin, esfenvalerate, cyfluthrin, or bifenthrin. Aerosol fog products can temporarily suppress infestations of flying insects, but these fogs will not kill pantry pests in food containers or protected locations.

Before using an insecticide, always make sure that the label says that the product may be used indoors and in kitchens. Never spray food, dishes, utensils, or cooking items with pesticides.

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