What to do about a horde of small flies.

Asked May 8, 2016, 9:39 PM EDT

There are dozens of small, triangular, approx. 1/4 inch long flies that circle almost endlessly on my porches. I set out:raw egg, honey and peanut oil, but had no attraction. The fly paper strips were avoided. I want to diminish the population! I can swat several before they stop landing in reach. They don't seem interested in anything other than circling with each other. What can be done? I am very restrained about using chemicals, but a good choice would be welcomed at this point. For what it is worth, I support Extension and so does my family. Thank you!

Lane County Oregon

1 Response

Your support is worth a lot. Thank you so much. These flies are a nuisance but not a danger. This is a mating swarm, so they only have one thing in mind just now. Usually the swarms are relatively short-lived. If you have a shop vac or a vacuum with a long hose, you can quickly diminish their numbers. In fact, it is almost a game to get house insects this way for me. Chemicals would be of very limited use in any case. Some people assert that ziplocks of water hung at the opening of the area will dissuade all flies. Not too sure about that one, but it might be fun to try. Not an officially researched opinion, of course. Let me know how it goes.