Casemaking Clothes Moths

Clothes moths were far better known to our grandparents than they are to most of us.  The use of synthetic fibers in carpets and clothing and increased sanitation has greatly reduced reports of this once common pest.  Clothes moth caterpillars feed on wool, leather, feathers, taxidermy mounts, and other items of animal origin.  
In Iowa there are two species of clothes moths may infest woolens and other animal fibers; the casemaking clothes moth (Tinea pellionella) and the webbing clothes moth (Tineola bisselliella). Casemaking clothes moth is the most common in Iowa. Casemaking clothes moth larvae spin a case that they remain in as they feed. The 1/2-inch long case incorporates bits of what they are feeding on and so is the same color as the fabric. Caterpillars are 1/2 inch long and white with brownish-black heads.
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. Caterpillars feed for 1 to 3 months before pupating. 
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 management should begin with thorough cleaning. Infested items that cannot 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. 

Cases of casemaking clothes moth caterpillars
Cases of casemaking clothes moth caterpillars with the colors of the wool rug they were feeding on.
Frass of casemaking clothes moth caterpillars
The frass of casemaking clothes moths is rather attractive with the different colors from the fabric.

Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Yard and Garden, and Iowa State University Extension and Outreach. If this article is to be used in any other manner, permission from the author is required. This article was originally published on January 15, 2016. The information contained within may not be the most current and accurate depending on when it is accessed.