Cluster Flies

Cluster flies can be important pests in Vermont homes when the sun begins to warm the southern side of our homes. They are often trapped inside the house and actively try to get outside. This species is a parasite of earthworms and are particularily active in the spring just after earthworms and robins appear. In the fall they look for a suitable place to spend the cold winter months. The move into our homes but do not reproduce until they are outside and find a host in the spring.

Cluster flies are distinguished from other flies by the presence of golden yellow hairs on the front, top of the thorax. Another noticeable feature of the Cluster Fly is the way its wings are held flat over its back while resting; the wing tips overlap when held in this position.

There are several ways to control cluster flies. Vaccuuming is a quick and easy method. Cluster Buster custer fly traps (web link below) have had some success in reducing obnoxious flies in the spring. In the fall the south side of homes and businesses with a residual insecticide has also be effective in reducing the number of overwintering flies the following spring.

For additional information check out the following sites.

University of Pennsylvania

http://www.ento.psu.edu/extension/factsheets/clusterflies.htm

Cluster Buster traps for Cluster Flies

http://www.powdertrap.com/

http://www.powdertrap.com/newsite/FAQ/answer.htm

http://www.cooperseeds.com/ClusterBuster.html