Could Carpet Beetles Eat My Shirts?

By Chris Williams on February 12, 2016.

A customer in Nashua, NH found several small-checkered beetles on her bedroom floor and a couple in her closet.  The same beetles were also found on the kitchen and dining room floor.  Her attic had just been re-insulated with some kind of blown in material, and the siding sealed for energy efficiency.  That is when she started noticing the beetles.  She really has not seen many beetles recently, so she did not worry about it.  Yesterday she was folding laundry and noticed that three of her shirts had small holes, all similar in appearance.  That is when she called her friends at Colonial Pest Control.  She is covered under the Semi-Annual Pest Control Maintenance Program, and situations like this are covered!

A:  I showed up met with the customer to figure out what was taking place.  Her house was very clean, no pet or small children.  There was vinyl and hardwood flooring downstairs and synthetic carpet on the second floor.  The attic was sealed shut after the new insulation and walls were all caulked and sealed.  Every thing looked ok.  In fact, she had purchased sticky traps on line for spider control, and they were in almost every corner.  There were some carpet beetles present, but only 3!  Since her main concern was the master bedroom closet, we headed up there to have a look.  Sticky traps in the dresser and on closed floor had no beetles on them!  She took out the clothes that she was concerned about and I was relieved.  The shirts were all the same material but different colors, stored in a very tight dresser, and mice were not an issue.  No evidence of beetles was noted in the dresser or anywhere in the closet; even the stacks of wool sweaters were fine.  I took a close look at the damage to the clothing but could not say for sure what might have caused it.  I did not look like carpet beetles were the culprit.  We took a tour of the house and in the basement; I found a brand new, high efficiency washer and dryer.  Some of the new dryers get super hot on the high, or cotton setting.  Materials like sheer rayon and other synthetic fiber can melt or disintegrate under high heat.  I looked at the label again, “90% Rayon”, dry on low heat or air dry.  Therefore, as it turned out, the dryer was cooking the three shirts and nothing else!  Carpet beetles can damage wool fabrics, rugs, and other material that contains keratin.  It is worth talking a little bit about the life cycle and control of carpet beetles.

Carpet beetles belong to the Dermestid family.  This broad grouping of beetles is responsible for large amounts of damage due to the wide range of materials that they are able to consume for food.  Museums and collectors of bones use Dermestid beetles as a means to clean skeletons.  Common members of the family Dermestidae include the furniture carpet beetle, the common carpet beetle, the varied carpet beetle, the black carpet beetle, the larder beetle, the hide beetle, and the warehouse beetle.  Some carpet beetle adults are attracted to pollen and nectar from flowers and may enter a home on cut flowers.  Once established inside, carpet beetles may continue to reproduce using food sources within the house.    Adult carpet beetles are small oval to slightly elongated, and have a checkered pattern of scales on the top or dorsal side.  The black carpet beetle is all black and more elongated.  Carpet beetle larvae are dark with hairy yellow stripes.  The hairs are arranged in tight patterns and stripes and may be ¼ inch long.  These slow moving worm-like larvae cast their skins when they molt.  Both the hairs and cast skins may accumulate at the food source.  Large infestations may present thousands of cast larval skins.  Cast skins and adults walking on windows may be the first sign of carpet beetle infestation.  Carpet beetles have a complex life cycle and undergo a complete metamorphosis (adult-egg-larvae-pupae-adult).  Adult carpet beetles live between 20 and 60 days.  Females lay up to 100 eggs on the larval food source, which hatch in 8-25 days depending on climatic conditions.   The larval period may be as long as 1 year (larvae do most of the damage), and pupation may take almost a month.    Carpet beetles chew holes in carpets and fabrics made of keratin.  Damage is usually concentrated in one area, unlike moth damage, which occurs as scattered holes.  Adults, larvae, and cast larval skins are found in the damaged area.  Carpet beetles are also the source of allergies among sensitive individuals.  Hairs from the larval skins can be quite irritating and may cause dermatitis, nasal and sinus irritation.  Dermestids feeding on hides and carcasses have also been implicated in the spread of anthrax bacilli.  If a carpet beetle infestation is suspected, a careful search for the food source is required.  Check carpets, stuffed furniture, stored fabrics, areas with accumulations of pet fur, hides, furs, tapestries, animal nests, garbage and debris piles, cut flowers or blooming flowers and bushes near unscreened windows.   Control of carpet beetles involves several factors.  Storage of fabric, woolens, and other potential food sources in sealed containers will prevent oviposition, or egg laying.  Avoidance of fabrics and furnishings of animal origin will prevent carpet beetle infestations, or limit their severity.  Tight fitting screens and doors will also prevent invader carpet beetles from ending up inside.  Animal and insect nests may also harbor carpet beetles and should be removed appropriately.  Sealing cracks to prevent the build of human and animal hair will also limit the breeding sites that are available to carpet beetles.  A strong vacuum or carpet cleaner will do a great job on carpets and rugs, be sure to clean both sides.  Steam cleaning, rug rotation, and washing in soapy water will also help control carpet beetles.  If these measures are not sufficient to control the infestation you are dealing with, the treatment for carpet beetles is very effective. The Pest Control Professionals from Colonial Pest Control are licensed to make safe and effective treatments to control carpet beetles and any other household pests you encounter!  Give us a call at 1-800-525-8084 if you think you have a problem!  Thank You!



We’re not satisfied until you are. Learn More