I have a tractor and I put wood shavings down once a week and chovel the entire thing once a month. But I have FLYS like nobody's buisness!Inside the tractor they aren't so bad, I guess the birds eat them but outside on the ground it is insane! If there is a poop on the ground the flys are all over it like , well you know. I use sweet PZD in the coop. How do YOu deal with the flys?