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AUBURN, April 26---Some new homebuyers, usually within one or two years after the sale, become panic-stricken in the fall if they find tiny brown beetles crawling in their new home. Initially, only a few beetles may be seen; then they emerge by the hundreds from wall voids, under baseboards, behind electric outlets and everywhere. Being strong fliers, the beetles rapidly spread to all rooms of the house.

The foreign grain beetle, Abasverus advena, is the most common beetle found in new houses, says Xing Ping Hu, an entomologist with the Alabama Cooperative Extension System. These small, reddish brown beetles are about 2 millimeters long. One identifying characteristic of the beetle is the presence of a round knob on each front corner of the thorax.

"Despite their name, foreign grain beetles are not normally associated with grain or other stored products. They feed entirely on molds and fungi," says Hu. If they are found infesting stored grain, the grain is damp and moldy.

When new homes are built, rain and moisture may fall onto wood frames before the roof and walls are added. If enough moisture has accumulated on the wood, on sawdust left in wall voids after construction, or on bales of straw used as insulation material in walls, surface fungi may grow on them. Foreign grain beetles may find some of these homes and begin to feed and breed on fungi and molds.

After many months, the beetles within the walls grow and move out of the wall voids and are attracted to windows and lights. Large numbers often occur in August and September in Alabama. They can continue to emerge from the walls of a new house for an extended period of time until the home completely dries out, says Hu.

The foreign grain beetle also inhabits older houses in which high moisture conditions promote fungal and mold growth. Beetles may enter homes through screens or through cracks and crevices in walls to locate mold. Adults have an average life-span of 230 days. These mold-feeding beetles sometimes are found in decaying plant materials.

While foreign grain beetles are a nuisance and an annoyance, they pose no harm to new homes or homeowners, says Hu. They do not bite, sting, spread disease to humans, or damage plants, wood, fabric or food. They are not a pantry pest.

Problems with foreign grain beetles are usually temporary. Most new homes dry out naturally within the first few years and the fungi, mold and beetles disappear. If leaky pipes within a wall exist in an infested house, these should be corrected immediately.

Homeowners can enhance the drying of a new house by using fans and air conditioning to discourage and eliminate growing mold and fungi. Timely repair of plumbing leaks and condensation problems also helps.

Beetles inside a home can be vacuumed or swept up and discarded. Common flying insect aerosol sprays containing pyrethrins can provide a rapid relief, but

repeated treatment is needed to kill newly emerging adults. Complete control can be achieved by locating the infested wall areas or source of dampness and injecting residual aerosols or dusts into cracks and crevices along the baseboards and into the wall voids.

For more information on the foreign grain beetles, contact your county Extension office and ask for publication ANR-1203. Homeowners can also view the publication and others on home pests on the Alabama Cooperative Extension Web site at www.aces.edu.

Click on publications and type in publication number.