Based on casual observations cluster flies seem to be attracted to light colored buildings.
Cluster flies behind the siding.
You will have to repeat the process every two years.
Cluster flies especially love decomposing food and sweets.
The cluster fly is a parasite of earthworms and in the spring and summer they breed outdoors in fields and lawns.
A contact pyrethrum spray like cb 80 which is approved for indoor use can help as well.
To prevent cluster fly infestation you could use following tips.
Fill all the cracks or crevices in walls window or door frames with caulking.
To get rid of existing cluster flies many people simply vacuum them up and empty the vacuum outdoors.
You can easily tell the two apart by the metallic sheen of a bottle fly vs.
Select an insecticide dust labeled for cluster flies such as ecovia wd.
Then fill a bellow hand duster halfway with the dust.
Make sure to seal every possible hole or crack like around windows doors siding behind chimneys utility pipes underneath the fascia etc in the building.
To prepare for the next season you can spray areas where you suspect these pesky flies will cluster.
Cluster flies pollenia rudis also known as attic flies are those large sluggish and noisy flies you find clustered in large numbers around your windows on warm sunny days in the winter and spring.
If the siding of the building is tight then the flies have less oppportunity to make their way into the structure.
Siding is purposely put up loose for expansion and contraction and so your duster tip or injection straw usually fit nicely.
Using a crusader you can puff small amounts up under the exterior siding into any cracks or crevice common to log homes and into all crevices they might choose to use for hibernating.
On the homes siding in the attic and deep in the wall voids where cluster flies like to nest should be dusted with drione dust.
Cluster flies vs house flies.
The bottle or blow fly is much larger than cluster flies and significantly faster.
Spray it lightly as needed for contact kill.
This is the spot i ll dust most often for pests like scorpions or occasional roaches for ants i most often use a non repellant spray such as arilon termidor or other and don t even worry about getting a product up and under.
Insects such as flies are naturally drawn to vinyl siding because vinyl siding attracts build up of airborne sugar particles from nearby trees plants and brush.
Replace the cap of the hand duster and turn the duster upside down so that the cap is facing the floor.
The dull colors and yellowish thoraxial hairs of the cluster fly.
That s why adding it to house paint is not such a good option.
You are now ready to apply the dust around the home.
With brick or stucco siding you can concentrate on the cracks and holes.