thank you chirp. my guineas are FIRED !!! tick #5 i have dusted but the rain wont let it stick around. i dont want to dust outside of the barn because on the off chance they do eat one i am afraid it will make them sick. so probably more antibiotics in my future. ok, that didnt even make sense to me. how is the rain washing the sevin out of the barn? need more coffee. lol anyway its not in there. humidity?