I have bought fly parasites for about ten years and they really do the job. I skipped a year once thinking that I had enough residual parasites from years past, but because flies reproduce at a much faster rate, I soon found out what a bad thought that was. I could not believe the difference. I had no housefly problem in the barn at all till I skipped a year. I found out the hard way just how effective these little wasps really are. They do not do anything to eliminate the horesefly population, only the housefly, which are what causes the horses to stamp their feet and ruin their hooves and get into their eyes, etc. I will never be without them at my barn again!

Pros: Keeps the housefly population down

Cons: Must be re-introduced every year

These are great! No chemicals, no pesticides!! all natural fly removers! They are little predator flies that eat fly larvae. We learned about them from our vet who was using them and he said they were good and we tried them and they work really good.

Pros: natural fly removers

Cons: none

I have not used these yet but have talked to people who have. I will try these in the up coming summer!

Pros: Helps eliminate flies!

Cons: The come back!

We've used the flies for 4 years and everyone comments on the lack of biting flies at our place.

Pros: Easy to use

Cons: price

This is very effective, especially when combined with fly traps (not the sticky traps).

Pros: good

Cons: n/a