Carpet Beetle Control: Protect Your Home
Scientific Classification: Anthrenus flavipes, Attagenus unicolor, Anthrenus scrophulariae
Named for their primary food source during the larval stage of development, carpet beetle larvae chew irregular holes into area rugs and carpets. While several species exist around the world, only three main species of carpet beetles are regarded as pests within our service area in the Mid-Atlantic region: the common carpet beetle, the furniture carpet beetle and the black carpet beetle. In addition to infesting homes, the pests invade warehouses, museums and similar locations.
What Do They Look Like?
Size: Most carpet beetles measure between 1/8 and 1/4 of an inch in length as adults. Larvae can also be as long as 1/4 of an inch.
Color: The coloration of carpet beetles plays a huge role in differentiating the various species. Some types of carpet beetles are solid in color, while others are multicolored. The most common shades include black, white, yellow and orange-red.
Characteristics: Oval in shape, carpet beetles feature vibrantly colored scales over their wing covers. The scales form distinct patterns that help distinguish between the different species of the pest.
Carpet beetles enjoy a widespread distribution throughout the world. North American carpet beetles populate the northern United States and Canada most heavily, but can be found as far south as Florida. Despite their heightened presence in the cooler northern regions of the continent, the insects cannot withstand cold weather without overwintering in homes or other heated buildings.
What Do They Eat?
Adult carpet beetles mainly feed on the pollen and nectar of various flowers. The insects cause the most damage during the larval stage of the life cycle when the developing pests feed on wool, feathers, leather, fur, hair, silk, museum specimens, dead insects and of course, the fabric of carpets.
A typical female carpet beetle will lay between 30 and 90 eggs in her lifetime. The eggs are deposited on or near a food source and take an average of three weeks to hatch. Uniquely, carpet beetles spend the majority of their existence in the larval stage. Larvae may be active for a period as short as two months or as long as two years, depending on factors like temperature, food quality and humidity. During this time, the pests go through 6 to 12 instars apiece on average.
Adult carpet beetles remain in the last larval skin for a brief period before reaching full sexual maturity. Some species begin to mate within a day of completing the entire life cycle. The lifespan of adults ranges from two weeks to several months.
- Look for adult carpet beetles congregating on windowsills.
- May notice large swaths of ruined material in carpets, clothes and other garments.
- Look for the light brown, shell-like cast skins of carpet beetle larvae.
Problems Caused by Carpet Beetles
When left unchecked, carpet beetle larvae can damage carpets, clothes, stores of grains, bed sheets, curtains and various other natural fabrics in the home. The pests can also cause serious losses for fabric manufacturers by infesting warehouses. In museums, the dietary preferences of carpet beetle larvae may lead to the destruction of priceless artifacts. Furthermore, the presence of the insects can result in the onset of dermatitis which causes an irritated rash to form on the skin of affected individuals.
Signs of Infestation
While it is common to spot one or two carpet beetles in the home on occasion, regular encounters with adults and larvae indicates an infestation problem. Attracted to flowers and plants inside the home, adults may congregate on windowsills looking for a way in. The most telling sign of a carpet beetle infestation is the damage left behind by the developing larvae. Carpet beetle larvae chew holes in clothes and other natural fibers often focusing on one large area of the fabric. The discovery of damaged carpets and clothes therefore signals the existence of a carpet beetle problem. Additionally, as larvae molt several times during development, the presence of cast skins means that an infestation is nearby.
The best way to prevent carpet beetles from infesting is to practice dedicated and good housekeeping. Always check flowers before bringing them into the home, and wash or dry clean second-hand clothes upon purchasing the items. Clean out of season garments such as winter coats before putting them in storage, and promptly wash sweaters.
Tips for Removal from Home
In the case of an established infestation vacuuming upholstered furniture, carpets and underneath furniture may effectively remove the pests. Particularly tenacious infestations may require the application of targeted pesticide applications which should be handled by a pest management professional with the certifications and experience necessary to properly and successfully eliminate carpet beetles from the home.
More Carpet Beetle Information
Are You at Risk of Infestation?
Carpet beetle infestations aren’t all that rare, but it’s important to catch them early to prevent damage to clothes, carpets, furniture and other upholstered items. Carpet beetles can easily chew through and damage a wool coat or natural fiber rug, making them a costly nuisance when they’re allowed to do their worst.
Carpet beetles come in a variety of shapes and sizes – the black carpet beetle is up to 3/8-inch long and is completely black, while mottled or spotted varieties are also common. They may lay eggs in natural fibers like hair, silk, wool or fur, and it is the larval beetles that feed on these items causing the damage. They find soiled items or clothing especially attractive, so piles of dirty laundry could be at risk.
According to Hope Bowman, Board-Certified Entomologist and Technical Specialist for S. Jersey / Philly, carpet beetles can infest anywhere, but are especially troublesome in homes with natural fiber carpeting which should be regularly inspected. “Sometimes we will see homes with hardwood floors that were carpeted in the past,” Bowman notes. “If there are remnants under heaters or out of sight, this could be a place where carpet beetles will infest.”
Other common areas Bowman sites include felt hats, the felt in pianos or pool tables and natural rugs. In cases where a rodent dies in a wall there can also be issues, and stored food products are occasionally infested. Regular housekeeping is the best form of carpet beetle prevention, but anyone can experience a problem with these small invaders. Once detected, it is essential to find and eliminate larvae which are the prime source of damage.
Will Your Rodent Problem Invite Carpet Beetles?
When mice or squirrels invade, one of their unsavory habits is to hide food in walls or other “safe” spots out of sight for human occupants. As if this isn’t problematic enough, they subsequently invite secondary pests like carpet beetles. Attracted by free food left behind when mice or squirrels are eliminated, carpet beetles, although not very common, can then cause damage to your property.
According to Hope Bowman, Technical Specialist and Board-Certified Entomologist for Western’s Philadelphia/South Jersey service area, drop ceilings, attics and wall voids can all contain food stowed away by rodents. When beetles run out of food in those locations, they then emerge to feed on natural fibers or cotton blends in carpeting or other materials, earning their moniker, “carpet beetles.”
At worst, carpets can be gnawed down to the weave. This, however, takes a long time and such damage is indicative of a major carpet beetle infestation. Carpet beetle problems, though infrequent are most often seen in old museums, taxidermy shops and offices. Luckily, killing adult carpet beetles is easy with a residual application. The trick is to find out where they’re coming from and eliminate the source.