The Lower Sac is fishing extremely well right now.  I fished with Harry & Van from Sebastopol.  We spent about half our day wading today and it was a blast.  We hooked over a dozen fish out of a single riffle in the afternoon.  The fish seem to like anything small (size 16-18) and black or green right now.  We had a huge hatch of PMDs from noon to 4:30pm.  It was a little too rainy for the fish to eat them on the surface, but they were sure chowing down on the nymphs.