The Case of the Bogus Carpet Beetles
This article was submitted by Barb Ogg, PhD, Extension Educator, University of Nebraska Cooperative Extension in Lancaster County. The article appeared in the Nebline Newsletter. Dates: August 1994 and updated October 1998.

Mrs. P. called our office with the following story. She was cleaning an old sofa in the basement of her house and lifted a seat cushion. Under the cushion, there were small, hard, black, seed-like objects. There was also a small hole in the corner of the cushion. After further examination, she found similar objects in a leather cowboy boot laying on the floor near the sofa. Puzzled by this, she called a nationally known pest control company for advice. They sent a service technician who inspected the objects from the sofa and boot. He informed Mrs. P. that these were carpet beetles, and the whole house would need to be treated each month with an insecticide for the next year. This treatment would cost $99 for the first treatment and $33/month for the next 11 months. (That's a total of $462!) 

After pondering this over, Mrs. P called our office. She wanted to know why the whole house really needed to be treated when the infestation was only found in the basement. She was also concerned about using insecticides throughout the house, especially because her grandchildren visit frequently. 

We convinced her to bring the insect specimens to our office so we could be sure that they were carpet beetles. (Our general philosophy is that we prefer not giving insecticide recommendations over the telephone, unless we can be sure that there is a pest problem that warrants the treatment.) Mr. P. arrived at our office a little later with the "carpet beetle" samples. He also brought the damaged sofa cushion. 

Under the microscope, it was apparent that the "carpet beetles" were not carpet beetles at all. In fact, they were not even insects but were wildflower seed hulls! The hole in the sofa cushion was over an inch in diameter, much too large for carpet beetle damage. Based on these clues, we concluded that the culprit was probably a mouse. After entering the house, the mouse stored wildflower seeds under the cushions of the couch and chewed a hole in the cushion, perhaps to build a nest. At some point, the mouse ate the seeds and left the hulls behind. 

Because Mrs. P. said that it had been quite a while since the sofa was cleaned thoroughly, we cannot be sure how long it has been since the mouse left this mess. Our recommendation for Mr. and Mrs. P. was to forget the insecticide treatment, but try to catch the mouse. They needed to buy a couple snap traps, bait them with peanut butter, and place them behind the couch next to the wall. This solution is the proper one for this situation and is a lot less expensive than the one suggested by the pest control technician. 

Without discussing the competence of this particular pest control technician, the moral of this story is that it never hurts to get a second opinion to make sure that the treatment is appropriate for the specific pest problem. This is true of pests in the home, garden and on the farm. Appropriate treatments are most effective and will sometimes reduce pesticide use and unnecessary exposure to you, your family and the environment. It can also save you money, possibly even hundreds of dollars! 

Not all pest situations that we work on are this memorable. But, if you have an insect pest problem that you are unsure of, call our office. We provide a free diagnostic evaluation and discuss best, least-toxic control options with all Lancaster County residents (including pest control company personnel). If we cannot identify it, the sample can be taken to the UNL Diagnostic Laboratory. They charge the public $5 per sample, still a bargain for accurate pest identification.

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