Advice for the Home Gardener from the Contra Costa Master Gardeners' Help Desk
Client's Questions and Concerns:
Client called about finding a “wormy” bug in the wood frame of her son's bunk bed. She wanted to know what it is and what she should do about it. We told her that we could probably identify the bug if she submitted good photos, but that the fastest way to get a positive identification of the bug would be to bring it to the CCMG Help Desk office in a closed plastic envelope or sealed jar.
Response from the CCMG Help Desk:
Thank you for dropping off an insect for identification at the Master Gardener help desk. The insect you left us is a carpet beetle larva. Carpet beetles belong to the family of beetles known as dermestids. There are three types of carpet beetles commonly found and of concern-- Varied (Anthrenus verbasci), Furniture (Anthrenus flavipes), and Black (Attagenus unicolor). All three carpet beetles are pests in warehouses, homes, and other locations where suitable food exists. Adults lay eggs on a larval food source such as woolen fabric or carpets or furs. Eggs hatch in about two weeks, and the larvae feed for varying periods, depending upon environmental conditions. Damage occurs during the larval stage only. Larvae feed in dark, undisturbed locations and on a variety of dead animals and animal products such as wool, silk, leather, fur, hair brushes with natural bristles, pet hair, and feathers; occasionally they feed on stored products such as certain spices and grains. They don't feed on synthetic fibers.
Varied carpet beetle
cast larval skin (left)
& adults (ctr & rt)
Carpet beetles are among the most difficult indoor pests to control because of their ability to find food in obscure places and to disperse widely throughout a building. Successful control depends on a combination of sanitation and exclusion. If sanitation and exclusion are successful, insecticide treatments aren't required. If you have found just this one larva, you probably don't have an extensive infestation.
Furniture carpet beetle larva (lt)
& adults (ctr & rt)
Elimination includes the accumulations of lint, hair, dead insects, and other debris that serve as food for carpet beetles. Throw out badly infested items. Remove old spider webs and bird, rodent, bee, and wasp nests, which can harbor infestations. Be sure that window screens, doors, and vents are secure to keep carpet beetles from flying in from outdoor sources. Regular and thorough cleaning of rugs, draperies, upholstered furniture, closets, and other locations where carpet beetles congregate is an important preventive and control technique. Frequent, thorough vacuuming is an effective way of removing food sources as well as carpet beetle eggs, larvae, and adults. After vacuuming infested areas, dispose of the collected material and/or bag promptly, because it can contain eggs, larvae, or adult insects.
Black carpet beetle larva (lt)
& adult (rt)
Here is a link for further information from the University of California about managing carpet beetles: http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7436.html
Please contact us again if you have more questions.
Contra Costa Master Gardeners Help Desk
Note: The Contra Costa Master Gardener Help Desk is available year-round to answer your gardening questions. Except for a few holidays, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523. We can also be reached via telephone: (925) 646-6586, email: firstname.lastname@example.org, or on the web at http://ccmg.ucanr.edu/Ask_Us/