Carpet beetles feed on animal and plant substances such as wool, fur, feathers, hair, hides, horns, silk, velvet, felts and bone as well as seeds, grain, cereals, cake mixes, red pepper, rye meal and flour. Other substances include powdered milk, dog and cat food, leather, bookbindings, dead insects, bird and rodent nests, and even cotton, linen, rayon, and jute, especially when stained with spilled food and animal excreta. The larvae cause the damage, crawling from room to room and living behind baseboards and molding, and in heating system air ducts, dresser drawers, carpets, clothing and furniture. Feeding damage often occurs under heavy furniture or pianos and at carpet edges. Adult beetles fly readily in May and June. They are attracted to night-lights, and enter through an open window or door. Some may be brought in on cut flowers or in furniture that has been in storage or sent out for repair.
Adult black carpet beetles are oval and shiny-black with brownish legs. They vary in body length from 1/8 to 3/16 inch. Larvae, hidden when feeding, are golden to dark brown and about 1/2-inch long. The body resembles an elongated carrot or cigar with a long brush of bristles at the tail end.
Adult varied carpet beetles are about 1/10 to 1/8-inch long and nearly round. The top body surface is usually gray with a mixture of white, brown and yellow scales and irregular black cross bands. The bottom surface has long, gray-yellow scales. (These scales are 2-1/2 to 4 times as long they are broad.) Larvae are about 1/4-inch and light to dark brown. The body is wide and broader at the rear than the front.
Adult common carpet beetles are about 1/10 to 1/8-inch long, nearly round, and gray to black. They have minute, whitish scales and a band of orange-red scales down the middle of the back and around the eyes. Larvae, frequently moving rapidly, are elongated, oval, reddish-brown, about 1/4-inch long and are covered with many brownish-black hairs.
Adult furniture carpet beetles are about 1/16 to 1/8-inch long, nearly round and whitish checkered with black spots, each outlined with yellowish orange scales. These scales are broadly oval and two times or less long as broad. The legs have yellow scales. The bottom surface of the body is white. Color patterns vary. Larvae, frequently crawling rapidly, are about 1/4-inch, elongated, oval and covered thickly with brownish hair.
All carpet beetles pass through the egg, larva, pupa and adult stages. Adults fly readily and during warm, sunny days feed outdoors on flower pollen of spirea, dogwood, crepe myrtle and buckwheat that have white or cream-colored flowers. Others feed on daisies, wild asters, etc. Adults are attracted by light, fly into homes and may be found on windows and screens. Depending on the species, each female can lay up to 100 white eggs or more that hatch in 8 to 15 days in warm weather. Eggs laid indoors occur in lint accumulations near the food source, in air ducts, under heavy furniture, underneath baseboards, etc. After hatching, larvae begin their destructive feeding, avoiding light, and molting several times as they develop. Sixty days to a year or more may be spent in the larval stage feeding, depending on food and temperature. When rooms are warm indoors, the life cycle is shorter than in an unheated portion of the house during the winter. In the spring, new adults follow the pupa stage. Usually there are three to four generations per year.
Pest Control Measures For Carpet Beetles
Locate the source of infestation before treatment. Carpet beetle larvae prefer to feed in dark, undisturbed, protected places. Use a flashlight and spatulato check in such places as under baseboards, in and under upholstered furniture, piano felts, air ducts, stuffed animal trophies, stored cereals, bird nests under eaves, rodent nests, wasp nests in attics, dead birds or rodents in wall voids, woolens, clothes closets, furs, etc. Often the cast skins are more abundant than the larvae. Adult beetles flying around windows may help in locating the infestation.
Good housekeeping is critical. Use a vacuum cleaner to remove lint, hair and dust from floors, shelves and drawers. Periodically brush, air outside, or dry-clean furs, woolens, blankets, etc. Clean rugs, carpets, draperies, furniture, baseboards, air vents, moldings and other hard-to-reach places regularly. Cedar-lined closets and chests help but are not 100 percent effective. Any tight box or bag that can be sealed is a good storage container. Be sure that all cloth goods are dry-cleaned, washed, pressed with a hot iron, or brushed prior to storage. Fur storage in cold vaults is effective. Remove and destroy abandoned bird and insect nests in attics, under eaves, etc.