Cluster Flies: Why Managing Them NOW Is Critical.

Cluster fly on daisyHave you ever come home to what seemed like a house full of dead flies all over the window sills – in the dead of winter!?  If that has happened to you, then you have experienced a cluster fly infestation. Fortunately, this is not your common icky house fly. You know, the gross ones that land on your BBQ dinner and lay eggs in your trash. Yuck!

Not Your Average Fly

Cluster flies are actually a parasite of earthworms and thrive in areas where there is fertile soil. They do not transmit disease. Cluster flies are generally just considered a nuisance when they decide to move into your house in the fall. They enter through cracks and crevices. Then they “cluster” together for warmth in wall voids and in your attic, to ride out the long cold winter. They usually go unnoticed till one warm winter day, when they are fooled into thinking it is spring and start seeking a way back outside.  

As a result, we tend to get a lot of calls in the winter, during those unusually nice days, concerning the “dead flies everywhere!” While we can try to help in some capacity in the short term; by helping you seal up all the cracks and crevices on the interior of your home and cleaning up the mess – the real solution to this problem comes about six months or so later.  Right about now actually!

The Modern Solution

Preventing cluster flies from entering your home in the first place is your best bet.  Once they enter, eliminating them means you will have a large quantity of remains to clean up or risk attracting additional pests to their carcasses.

As late summer approaches, hiring a pest management professional to inspect and treat the exterior of your home, will greatly reduce the number of cluster flies you will see the following winter. This approach will help to eliminate the adult flies that are drawn to your home for the warmth.  

However, it is all about timing with this treatment. Too soon and the material will break down and become ineffective before doing the job. Too late and the cluster flies will have snuck in to your home to bunker down for the winter. So calling your local pest professional today to determine the best time to treat this summer is critical!


So if you have encountered “dead flies everywhere” – be prepared. Contact Modern Pest Services today! Our HomeCare Green program provides year-round pest protection, covering 60 common pests – including Cluster Flies!  Call 1-800-323-Pest.