I clean them were they fall, the deer doesnt seem to mind. Last friday morning I shot a wolf in a clear cut, lots of blood arround, went back that evening and shot a nice 4 point buck on the same clear cut, about 500 yards from were I shot the wolf, gutted it out there and the following day my dad shot a 5 point buck off of the same clear cut. The blood and gut pile didnt seem to make ANY difference.