Yup, the Aug/Sept Reiter beater. I've had particular success on a size 8 olive whooly worm and green cary special; also have seen success with the prince nymph. These are all dark green patterns and I've seen green insects rising off of the water at Reiter during this period; the steelhead may be snapping at these guys (although probably not feeding).

Black, brown, dark green, small, and buggy looking seems to be the ticket. Also pays to use a rod that has enough forgiveness to keep a size 8 hook from straightening out or a 6 lb leader from snapping.

Good Luck