what to do about cluster flies?

Asked August 18, 2017, 3:56 PM EDT

The last few days we've noticed large, kind of sluggish flies showing up in our house trying to get out of the window. We've probably had a dozen over the last few days. Internet research suggests we've got cluster flies. What do we do to get rid of them and to prevent any more from showing up. How can we possibly figure out where they are nesting in our house?

Montgomery County Maryland insects indoors cluster flies

1 Response

Here is our website on cluster flies. http://extension.umd.edu/hgic/soils/soil-testing
Adult flies usually enter homes in late August to overwinter and occupy attics and/or wall voids that are warmed by winter sun exposure (most often southern). They are parasites of earthworms.
You need to look and see how they are getting in and seal up. The least toxic control is to vacuum them up.

mh