Did you ever take a sweater out at this time of year and discover holes that weren't there before?

You may have blamed clothing moths, but the real culprits were likely carpet beetles.

They are not a garden pest. The adult beetles feed on pollen of garden plants, especially those with plentiful pollen. Cut flowers are one way carpet beetles find their way indoors. Inside the house, the larvae of this innocuous garden insect can be a damaging household pest.

The adult beetles are relatively small, 1/10-inch long, with round black to brown bodies. The varied carpet beetle is most common in our region. It has lighter horizontal bands across its back. The adults live two to six weeks. Before they die, the adult females seek out food sources, then lay about 40 eggs in a promising area. The larve hatch in 10 to 20 days.

They thrive on some type of protein, usually animal derived. This includes wool rugs, woolens, silk, animal skins, furs, real stuffed animals, leather, feathers, down and animal horns.

Another potential food source is wool felt. They can cause significant damage to infrequently played pianos by eating the felts.

Carpet beetle larvae also feed on animal hair, including keepsakes or crafts made with real hair or hair in old hairbrushes. They also feed where pet hair collects, such as underneath furniture or in air ducts.

A big part of the carpet beetle larvae's diet is dead insects, often in light fixtures, window tracks, deserted wasp nests and insect collections. They'll also feed on dead birds or rodents.

Carpet beetle larvae even can be found infesting long-stored, unused dried food products that contain protein such as creamy noodle, pudding and cake mixes. Dried pet food also is a candidate for infestation.

Some sources will tell you that carpet beetles don't eat synthetic fibers. Wrong! They will attack synthetics and cotton if the clothing has been put away unclean. They typically do more damage to synthetic materials or blends. That's because they need to eat more to meet their needs.

It's kind of scary to think of the items that carpet beetles can attack, but they're not a pest that will cause widespread destruction. They prefer the privacy of dark, out-of-the-way places.

It can take 200 to more than 600 days for them to mature, depending on the quality of the food and the temperature.

Homeowners will occasionally run across adult beetles, but they're most likely to find the larvae. The golden brown larvae have a tapered, 1/4-inch long or shorter wormlike body that's covered with tufts of bristly hair. As the larvae grow larger, they molt, leaving empty skins behind. These skins and their frass (poop) resembling sawdust are often evidence of a carpet beetle infestation.

If you find a carpet beetle infestation, there are some easy steps you can take.

With clothing, launder the garments.

Have infested carpets cleaned.

If found in food, throw it away. Inspect other nearby potential food sources for signs of infestation.

Clean the area of an infestation by vacuuming and wiping surfaces with soap and water. If they are in an item that can't be easily cleaned, such as a hide or craft item, put it in a sealed plastic bag and freeze it, then thaw it. Repeat this three times in two days. Or place the bag in a deep freeze below 18 degrees for at least two weeks. You also can do this to protect dry food products from infestation.

* Marianne C. Ophardt is a horticulturist for the Washington State University Cooperative Extension Office in Benton County.