Uninvited Guests

(This column first appeared in the March 22, 1999 Buffalo News.)

   The questions are already coming in: "We found this insect walking across our living room rug. What is it and how can we prevent such bugs from entering our house?" "What are the flies that gather on our windowsills this time of year ?" "While doing repairs I removed some insulation and found hundreds of little orange bugs swarmed on the exposed wall. What should I do about them?"

   Each year at this time I get a few of these inquiries and Wayne Gall, entomologist at the Buffalo Museum of Science, receives many more. So in this column I list the six most common culprits and suggest what you might do about them.

   Newcomers to the Niagara Frontier are western conifer seed bugs. In less than ten years they have already become widespread. As their name suggests, they feast on pines, spruce, fir or hemlocks, sometimes entering a nearby home. These 3/4 inch bugs have flattened areas on their hind legs that look like cowboy chaps and a zig-zag white line across their back. (A beautiful woodcarving of one by Mark Carroll of East Aurora is in the museum library.) When picked up, they defend themselves by emitting a pungent odor.

   Boxelder bugs are slightly smaller. Their bright red bodies are mostly covered by their brownish to black thorax and wings but red stripes do show on their back. Their head is black. In fall and spring these bugs often collect in large numbers on buildings in sunny locations and some make their way inside. If there is a boxelder (a.k.a. ashleaf maple) tree near your home, expect to find them.

   About the same size and quite similar in appearance are milkweed bugs, also orange or bright red, but this species (the small milkweed bug) has three black areas on the back and black spots on the underside. Like monarch butterfly larva, they have spent their early lives feeding on milkweeds.

   Those are all bugs but other insect families are also represented.

   Cluster flies resemble house flies but this species overlaps its wings above its back when resting. Where numbers of them "cluster" (often at a window) a sweet but acrid odor is evident.

   Eurasian multicolored lady beetles were imported to control pest aphids on crops and ornamentals, but they can gather in very large numbers on and inside houses. Most readers are familiar with the almost circular shape of "ladybugs" and their orange or red coloration, but while other species may be identified by the number of black dots on their backs (a common native variety is thirteen-spotted) this orange-colored species varies from no dots to many.

   Those are all relatively benign insects but now come the villains of the group: elm leaf beetles. Familiar to Buffalonians whose elms are attacked, this species has fortunately been less populous for several years. At a quarter inch they are about lady beetle size, but dull green or yellowish often with a black stripe along their sides.

   None of these uninvited guests damage your house or your possessions. There are plenty of other home invaders -- carpenter ants and carpet beetles, clothes moths and cockroaches, houseplant lice and grain beetles -- fulfilling those roles. Instead, these insects are merely taking advantage of the same warmth and protection that our homes provide us. They have spent the winter hidden in hibernation-like diapause and now seek only a way out-of-doors. Open a window on a warm day and they will depart without a word of thanks for your hospitality. (But vacuum up the elm leaf beetles and destroy the bag.)

   And think now about caulking cracks and crevices to prevent their return next year. -- Gerry Rising