Tuesday, April 16, 2013

Carpet Beetles and Other Home Invaders of the Creepy Crawly Kind by Patti O'Neal

Ah Spring!  The weather is changing, nature is applying a little moisture, things are just starting to green up and garden bulbs are threatening to break bud.  But while nature is moving and shaking outside, a bit of it is “happening” indoors as well. 

Insects begin hatching and seeking warm, food rich environments, or in the case of some, moist environments bringing them indoors; some doing damage, some not.  Knowing when or even if you should panic is important. Most are benign and can be handled easily even if an infestation occurs.

Adult Carpet Beetle photo by Joseph Berger, Insectimages.org
One of the most common insects found in Colorado homes is the Carpet Beetle.  These insects have extremely diverse feeding habits. Some species prefer high protein materials of animal origin, so will feed on dead skin, hair, feathers of animal or humans or insect parts.   Other species will develop and feed on seeds, grains, herbs and other materials of plant origin. 

Carpet Beetle Larva photo by Joseph Berger, Insectimages.org
It is the larval stage of these insects that does the greatest damage to carpets, and other household fabrics including clothes.   They will chew holes in these materials, with the damage concentrated most likely in one area unlike clothes moths which cause damage in spotty patterns on fabrics.  The fabric strands are cleanly cut and the area relatively clean of insect frass (fecal material) as opposed to the clothes moths damage which appears more cluttered and littered with the insects fecal material and cast skins.  The larvae of the carpet beetle are slow moving and are characteristically hairy or bristly. 

Indirect strategies for controlling these insect invaders include: Making sure stored clothing is cleaned before storing and using tightly sealed storage bags and boxes.   Likewise, food products such as grains, cereals, pet foods and other susceptible substances should also be stored in airtight containers.

Choose small area rugs that can be cleaned regularly, as opposed to wall to wall carpets when possible.  Clean and dust frequently to eliminate dust mites and be sure to clean under and behind furniture. Remove bird nests after fledging from under eaves or on house, repair holes in screens, caulk cracks and crevices that can become breeding grounds as they catch lint, pet hair and other organic debris.  Vacuum frequently, keep fabrics clean. 

Another common invader found in both Spring and Summer in Colorado homes is the Duff Millipede. 
Duff Millipede photo by Whitney Cranshaw, Insectimages.org

Often misidentified as a carpet beetle larvae, this insect is actually much smaller.   It is only about 1/10 of an inch long, are oval, but much rounder than the carpet beetle larvae and have 13 pairs of legs and has a long pair of hair like appendages at it’s hind end.  They look nothing like the typical millipede found in lawns.

These insects enter the home in the hotter, drier months of the year and will congregate in moist areas like drains, or leaky, damp areas of the house.  They will also be found near hot tubs.  Unlike the carpet beetle, these invaders do not reproduce in the home.  A typical home environment is too dry and will cause them to die, most likely within a few days after entering the house.  They feed on leaf/needle litter, algae or decayed bark.

To prevent them from entering the home, seal access areas and make sure drains, pipes and any sources of excess moisture are sealed or tightened properly.  

For a more complete description of Carpet Beetles and other control solutions, see Colorado State University Fact Sheet entitled Carpet Beetles at the following link:  http://www.ext.colostate.edu/pubs/insect/05549.html.
More information on the Duff Millipede can be found at:  http://www.ext.colostate.edu/pubs/insect/05552.html.