2017-11-15 / Gardening Tips

Household Insect Invaders

The week before last we had some summer like weather for a few days that could be characterized as “Indian Summer” in areas which had previously had frost. Indian summer has been defined as a period of warm weather following a hard frost. Now that MOST of our region had a hard or “killing” frost, we can look forward to more Indian summer. At least I hope so! I still have not cleaned up my garden yet and this is a chore best accomplished before I get too busy next spring. Sometimes we get Indian summer in October and sometimes it occurs in November. Much of the region did get a soaking rain last Sunday and Monday. I recorded four inches, but I saw on the news that Hunter Mountain got over six inches! When the seasonal numbers are “crunched” into “averages” it will appear that rainfall has been pretty near normal for the month of October but the fact is that it has been far from normal.

Beetles invasion

One phenomenon that often accompanies warm weather and sunny days in the fall was very evident last week, as hundreds of Lady beetles congregated on my house, doors and windows. They were trying to find a warm place to spend the winter.

There are several species of insect that exhibit this congregating behavior in the fall and they often become indoor pests all winter long. The main species of insects I have noticed this fall are ladybeetles, western conifer seed bugs (a type of stink bug), boxelder beetles and cluster flies.

Ladybeetles or ladybugs are generally considered beneficial insects since they feed on many different pests both as adults and even more so in their larval form. Unfortunately, the species of ladybug that has been so conspicuous here was imported from Asia and it has pretty much displaced the native species. The ladybeetle and these other fall invaders emit an “aggregation pheromone” that attracts others of their species. In some cases they are so numerous as to almost cover the sunny side of a building. Most of these insects are looking for a comfortable place to spend the winter and that means they may end up inside your house all winter in the wall voids or other refuges. When the heat is turned on they may sometimes wake up and fly around. Lady beetles can and do bite people on occasion and while not nearly as painful as a bee sting or as persistent as a mosquito bite, it is still pretty annoying.

The western conifer seed bug is often called a “stink bug” since it emits a rather foul odor when disturbed. I think it smells like citrus and do not find the scent all that unpleasant. The bugs are large, awkward and ungainly however. They have a long, shield shaped body, long legs, long antennae and what appears to be a large “W” on their back. As far as I know they do not bite but they are also very unwelcome in most houses!

Fewer cluster flies

Cluster flies look like large houseflies that often spin around on their backs resembling insect “break dancing.” In recent years I have seen fewer and fewer cluster flies, perhaps they have been displaced by the western conifer seed bugs?

Once these pests are inside your house or inside the walls and attic there is little you can do except vacuum them up as noticed all winter. Some businesses or institutions such as hospitals have their exterior walls sprayed with a preventive insecticide in late August or September but I am afraid it is a bit too late for that treatment right now. If you see theses insects congregating on a sunny outdoor surface you can spray them with an over the counter insecticide.

It’s da bomb

Every fall I use an indoor fogging “bomb” to kill the insects that end up in my unheated back room and sometimes I will use one in a shed. Although queen wasps and some hornets overwinter in houses, the vast majority of them perish after a ’ few nights in the ’20s. I am allergic to wasp stings and more than once I have been stung just opening the shed door and having a wasp fall on my head. These devices are effective but must be used very carefully since they can poison pets, contaminate food stuff and even start fires. If you decide to use one, read and follow all label directions very carefully.

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