Agree with Gulfstream, flies need to be bottom ticking heavy in chartreuse or various shades of pink. Other colors I've seen work occasionally are white, red, and yellow. On the Umpqua just look for a conglomeration of cars parked along the river and watch the crowds for a bit to get an idea what colors they're throwing and where. I usually look for deep runs and bounce small crappie jigs along the bottom. Last year I went with some friends of mine and they were fishing crappie jigs under a bobber with split shot to get the jigs down. Seemed to work for them and they didn't sacrifice quite so many jigs to the river rock gods.