Varied carpet beetle

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There are about six insect groups that can cause damage to fabrics. Larvae of carpet beetles (Family: Dermestidae) and clothes moths(Family: Tingiidae) are major pests because fabrics/substances of animal origin are major components in their diet.

In the northern states east of the Rocky Mountains, damage to fabrics is more likely caused by dermestid beetles than clothes moths. Dermestid beetles are more resistant to cold temperatures and lower humidities of the northern states.

In the southern states, clothes moths are more likely to be a problem because of higher humidities and temperatures. 

Insects of the remaining groups, crickets, silverfish, cockroaches and termites usually feed on substances other than fabrics. However, these insects will feed on fabrics, especially when the fabric has food or perspiration stains on it. 

After damage to fabric is discovered, it may take some detective work to determine the culprit. The insect pest is usually no longer present when the damage is found. To properly determine the pest, an investigator should make note of the following clues. 

1. Look for live or dead insects. Live insects may be hard to find because these pests avoid the light, hiding in the folds of the fabric or in the cracks and crevices of closets. You can sometimes find dermestid larvae by shaking the damaged fabric over the middle of a white sheet spread out on the floor. Live adult carpet beetles and clothes moths are rarely found because they do not feed on fabric. Carpet beetles adults sometimes can be found dead on window sills, and clothes moth adults do not feed. 

2. Look for cast skins, insect fragments and products. Cast skins of larvae are often found with damaged fabric or fur. If you need to remove insect fragments for identification, carefully place them in a small vial or tin and take them to an Extension diagnostic lab. Brittle insect parts break apart easily when placed in an envelope. Clothes moths will often leave silken webbing, cases, pupae or frass in the damaged fabrics. These "parts" will help identify the pest. 

3. Type of fabric. Carpet beetles and clothes moths can digest keratin, a component of animal hair, which includes wool, fur and feathers. Fabric made of wool blends may also be damaged. They also feed on silk. The other fabric pests tend to damage fabrics only if the fabrics are stained with food or perspiration. 

Carpet Beetles

Adult beetles are small and oval, have knobbed antennae, and scales or hairs present on their body. The colors of the scales or hairs produces color patterns that varies from species to species. The larvae have a tapering wedge-shaped body covered with hairs. Larvae of most species have a tuft of hairs at the end of the body. It is thought that carpet beetles evolved to feed on animal hair, fur, hide,and in the balance of nature, help decompose dead animals. Adults feed on pollen and are frequently found on flowers, again suggesting that members of this group are not well suited to living indoors. Some members of this group can also feed on stored products like cereals, nuts, dried meats and cheese. 

Dermestids can do considerable damage to woolen fabrics and rugs; fur; silk; leather and hide; hair; insect collections; and taxidermist's stuffed animals. These infestations may come from another source that is not obvious. Common reservoirs for dermestids are bird and rodent nests and old bee and wasp nests, where dermestid larvae feed on hair, feathers and/or dead insects. 

Dermestids may also feed on linen, cotton, rayon and jute, when these fabrics are stained. The most common dermestids attacking fabrics are varied carpet beetles, furniture carpet beetles, black carpet beetles, carpet beetles, and hide beetles. 

There are several species of moths that may damage fabrics. The clothes moths most likely to be a problem are: the webbing clothes moth and the casemaking cloths moth. 

The webbing clothes moth larva spins silk webbing on the fabric and feeds under the webbing. After going through several molts, it pupates and becomes an adult moth. The adult moth is about 1/2" long and creamy white with a golden tuft of hairs on its head. 

The casemaking clothes moth larva lives inside a tubular case that it constructs out of silk and fibers. The larva "drags" the case around with it as it feeds and will die if it is separated from its case, probably from desiccation. Again, a full-grown larva will pupate and turn into a small white moth. To repeat, clothes moths are uncommon pests in Nebraska. Small whitish-grey moths found in homes are most likely Indian meal moths. This insect is a pest of pantries, especially grain products. 

These other groups of insects can, but infrequently damage fabrics.

Crickets feed on vegetable material and damage fabric if there are food or perspiration stains on it. Both house and field crickets have been recorded to damage fabrics occasionally. Sometimes houses near dumps become infested with house cricket. Control for crickets usually involved removing mulches, leaves or other vegetation around houses and treating the perimeter with an insecticide. These insects need a constant moisture source; removal of moisture helps reduce populations. 

Silverfish feed almost exclusively on starchy materials and are more of a problem feeding on books and book bindings than on fabrics. They may eat fabric especially if it has been starched. Control involves removal of the food source, limiting water availability, and residual sprays. Dust can be used when treating attics and other undisturbed places.

Cockroaches are omnivorous. On occasion, they may feed on hair and wool fabrics, especially if stained with food and perspiration. 

Termites feed on cellulose and may feed on fabrics of plant origin. 

Control of dermestid beetles and clothes moths usually centers around prevention practices. Closets that are cleaned occasionally are less likely to be damaged. Clean fabrics should be stored in tightly sealed containers with paradichlorobenzene moth crystals. (Dry cleaning destroys all stages of these pests.) Chests and closets made of cedar repel fabric pests, but cedar loses its repellency over time. Cedar chests are not air tight. It is possible that fabric can still be damaged in a cedar chest. Mothproofing should be considered to protect expensive fabrics like oriental rugs. 

Caution: Insecticides can be used to destroy these pests, but direct spraying of fabrics should be avoided. Oil-based insecticides may damage fabrics, and water-based ones may cause woolens to shrink. Read label directions careful.

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University of Nebraska-Lincoln Extension in Lancaster County is your on-line insect pest and wildlife educational resource. The information on this Web site is valid for residents of southeastern Nebraska. It may or may not apply in your area. If you live outside southeastern Nebraska, visit your local Extension office