The clothes moth, once a well-known and common pest of fabrics in the home, is rarely encountered. Carpets made of synthetic fibers are not attacked by the clothes moths, and an increase in use of dry-cleaning and other sanitation actions have made the clothes moth an uncommon pest today.
Two species of clothes moths may infest woolens and other animal fibers. Casemaking clothes moth is more commonly reported in Iowa than the webbing clothes moth. The name of the casemaking clothes moth comes from silken tube, or case spun by the larva and carried about wherever the larva goes. The 1/2-inch long case incorporates bits of fabric and is the same color as the fabric. Caterpillars of both species are 1/2 inch long and white with brownish-black heads.
The clothes moth larva is the only feeding stage and therefore the only stage that damages fabrics. The larval stage lasts for 1 to 3 months during which time the larva eats only fibers or materials of animal origin. These include woolen rugs and clothing, hair, fur, feathers, taxidermy mounts and felt.
Clothes moth larvae prefer to feed in protected locations such as under collars, inside hems, on the backside or in cracks at the edges of woolen carpets, under furniture and inside storage containers. Rarely, if ever, will these insects be found infesting garments or items that are used or moved regularly. The larvae tend to crawl about as they feed and eat the nap from the fabric surface. If the larvae remain for a long time, deeper damage and holes may appear.
Adult cloths moths are buff colored and about 1/4 inch long. They are seldom seen; they avoid light and remain hidden. They do not feed or cause any damage.
Clothes moth control should begin with thorough cleaning. Infested items that can not be discarded should be dry-cleaned or washed in hot soapy water and dried at high temperature. Thorough vacuum cleaning will remove most of the larvae and eliminate loose hair or lint that may be infested. Special attention should be given to cracks, crevices, corners and underneath objects. If carpet is infested it will probably be necessary to lift the carpeting for cleaning and treatment.
Residual household insecticides can be used to treat cracks, crevices and other areas after the infested materials have been removed or cleaned. Follow label directions. For more information on insecticides please see "Insecticides for Indoor Use." While this can be a do-it-yourself project you may wish to hire a pest control operator for a single application plus follow up on an as needed basis. Contact a carpeting company concerning treatment of valuable wool rugs and carpets.