Carpet Beetles Fact Sheet No. 5.549 Insect Series|Home and Garden by W.S. Cranshaw* Various species of carpet beetles, Quick Facts particularly the black carpet beetle, are commonly found in Colorado homes. Low- • Carpet beetles are one of the level infestations are of minor importance. most common insects found in Occasionally, severe infestations occur in Colorado homes. food products, stuffed animals, woolen • Carpet beetle larvae feed fabrics, feathers and other items of animal origin. These require thorough treatment. and develop on a variety of The name “carpet beetle” comes from their materials including most stored former importance as a pest of woolen food products and anything of carpeting. They do not feed on carpet made animal origin. from synthetic fibers. • Many infestations originate from wild populations of Appearance beetles that move into homes Adult carpet beetles are oval and during warm months. approximately 1/8 inch long. The black • Prevent and control carpet carpet beetle is uniformly dark brown-black Figure 1: Adult and larva of a Trogroderma species beetles by cleaning up spilled and shiny. Other common carpet beetles dermestid beetle. food and accumulated lint, (varied carpet beetle, furniture carpet beetle, common carpet beetle) are covered with storing susceptible items in colored scales of various patterns. insect-proof containers, and Carpet beetle larvae are elongate, reddish insecticides when necessary. or light brown, and covered with short hairs. Some species have distinct tufts of hairs extending from the posterior. Larvae repeatedly shed their skins and these old larval skins are often confused with the living insects. Full grown, larvae are about 1/8 inch long. They bear a superficial resemblance to duff millipedes, discussed in fact sheet 5.552, Millipedes, Centipedes and Sowbugs.
Life History Most carpet beetles occur as wild populations in Colorado. The larvae feed Figure 2: Black carpet beetle adult and larva. on various materials of animal origin and commonly occur in bird nests. Adult beetles populations. Carpet beetles also may be feed on the pollen of plants, with Spirea carried about by moving infested items. reported to be one plant that is particularly Inside the home, the female beetles lay favored. Presumably, most household eggs over a period of two to three weeks. © Colorado State University infestations originate from these wild Common egg laying sites include areas Extension. 1/00. Revised 7/14. where dead insects occur, in accumulations www.ext.colostate.edu *Colorado State University Extension entomologist of lint in air ducts, along edges of and professor, bioagricultural sciences and pest carpeting, underneath baseboards, and management. 7/2014 similar locations. Prevention and Control Several steps can help limit the occurrence of carpet beetle infestations. Regular cleaning of spilled food and accumulated lint eliminates primary breeding sites. Store food, woolens, furs and other susceptible items in insect-proof containers to prevent access by the larvae. During warm months, the adult beetles can be largely excluded by using screens and Figure 5: Larvae of carpet beetles. Figure 3: Furniture carpet beetle adult and larva. sealing other openings. When a carpet beetle infestation is Thoroughly clean the house when suspected, closely examine preserved carpet beetles are detected. Pay particular animals or hides for live larvae or cast attention to areas where lint accumulates skins, as carpet beetles frequently infest and move furniture occasionally to expose these objects. Check all areas where possible hidden breeding areas. lint, especially dog or cat hair, tends to accumulate: areas under carpets and along carpet edges; under seldom-moved Chemical Controls furniture; in floor cracks, registers and It is sometimes useful to treat infested ducts; and in folds of upholstered furniture. areas with insecticides to eliminate residual Check stored woolen clothing, flannel populations of carpet beetles. In nonfood and woolen yarn in attics, basements and areas household formulation of various Figure 4: Old skins of varied carpet beetle larvae. closets. Look through food products stored pyrethroid insecticides can be used. for long periods without use. Other possible Numerous products allow such use and breeding sites are old animal or bird nests contain as the active ingredient permethrin, The eggs hatch in 10 to 20 days and that may be in the house, and collections of bifenthrin, deltamethrin, tralomethrin and the newly emerged larvae search for food. dead insects around windows. related compounds. Use according to label Depending on the quality of the food When you find the source of the directions and pay particular attention source and the temperature, the larvae problem, remove and destroy the infested to treating baseboards, corners, edges of become full grown in two to 11 months. material if possible. Objects which cannot carpeting and other areas where lint and If a food source disappears during the be discarded should be treated to kill eggs other debris accumulates that is fed on by insect’s development, the larvae can survive and larvae. Store small items in a freezer for carpet beetles. for several weeks without food. Many 48 hours or heat-treat them at temperatures Insecticides should only be used in carpet beetle larvae are quite mobile and above 120 degrees F for several hours. addition to a thorough cleanout of potential can wander a considerable distance from Dry-clean infested clothing. Put infested breeding sites. Most household insecticides a primary infestation. The most common nonfood materials in a plastic bag with a will provide some residual effect for control carpet beetles in homes have a one-year “pest-strip” for several weeks. Elimination but carpet beetles may reinfest from life cycle. Adults and wandering larvae are of carpet beetles from large objects, such outdoor sources during the warm season. most commonly encountered in late winter as furniture, may require the services of a and early spring. professional pest control operator.
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