In my yard there are always 100's of flies. they hangout on our car and other things in yard. Anyone know why?

there is nothing dead around and our garbage is confined. we do have about 8 trees in our yard, not sure of what type they are. I know they are very tall and have like yellowish flowers in the summer time. in the fall- the little 'helicopter' things that fall off and spin in the air, they have like two beans inside. they are green and turn brown after they have fallen. i think maybe like the ones from maple trees? not sure though

the flies have yellowish 'butts' and their eyes are a reddish brown, they are of average size.

I live in up-state NY around the Rochester area

In my yard there are always 100's of flies. they hangout on our car and other things in yard. Anyone know why?
Firstly, the tree is possibly a sycamore maple. I know moths sometimes lay their larvae in maple trees. However, there are some flies which may fit your description: the deer fly; the horse fly; and, oddly enough, the yellow fly. If you get a lot of 'mosquito' bites, these will, in fact, be the culprit. The flies like shaded wooded areas (provided by the trees), and the males feed on nectar. I advise you get a fly lamp, and some repellent. The sites I listed give useful information.
Reply:We live right near you. :O) We used to hose down the yard alot but better done in early morning or evening.We used a nuetralizer that attaches to the hose.They sell products also that trap flys in jars.It works great but it works so great that they were attracting more flys from the neighborhood. good luck.
Reply:something is attracting them. look to see where a lot are landed and get rid of what ever that is.
Reply:The best way to keep flies away is to put water in a clear plastic bag and hang it from a tree or trellis. It really works..........
Reply:You can kill them by the thousands by putting out some small bits of raw beef in mayonais jars that have a 1" hole punched in the lid. Do it on a warm sunny day, the inside of the jar gets up to 120 degress, the flies are drawn into it one after the other and will not leave, they die in 30 seconds from the heat. put four our five out and the jars will be full in one hour if the infestation is bad.