Summary: Sometimes there is little we can do to avoid an insect invasion, especially when a structure happens to be directly in the way of a migratory flight path. Batten down the hatches and grit your teeth until it passes over. Trying to exclude migratory insects can be maddening.
Stacey; Brunswick, Ohio asks:
I have two questions. When the weather starts to warm up like on a warmer day in winter, we seem to get a house fly or two in the house. Does this mean they are "hibernating" somewhere in our house, or do we have an extreme number of maggots somewhere waiting to hatch?
The other question has to do with lady beetles. They also emerge on the warmer days and I find myself killing several a day. They may be originating somewhere near a basement window because when we sprayed the basement, there were quite a few dead ones on the floor in the same corner near the window. What should I do? Do you think an exterminator is
needed and is it safe to have a treatment with a baby in the house? Thanks!
My guess is the flies and lady beetles are migrating from locations outside your house and happen to be landing on the south or west walls of the house. Those are the sides of the house that face into the sun and usually warm the fastest. The migrating insect walk up the outside walls until they find a crevice in the siding. From there, they make their way inside the walls.
This is a common occurance with cluster flies. The flies breed in the ground, laying their eggs in earthworms, so there is nothing you can do to treat the source. The flies and the beetles can be migrating from far away and your
house just happens to be in their flight path.
You can have the outside walls of the house treated and the treatment will help to some extent, but it will not guarantee total exclusion. You can try to seal up cracks in the sides of your house, but that, also, is nearly an impossible task. You should check the attic to make sure you vacuum up what insects you discover. Cluster flies can overwinter in the attic and start to get active when temperatures rise. You might also consider setting off a total release aerosol "bomb" to kill the insects in the attic. These devices are available at most hardware and grocery stores.
A note of caution. Before you start releasing pesticides into the air make sure you cover aquariums and remove your chidren and pets. Give the house about three or four hours to ventilate before you return.
Insect flight patterns change over a period of time and the problem often resolves itself. However, if you want to be pro-active get out your ladder, caulking gun and pesticide sprayer and go to town.