R. M. Nymph
Pattern information
There are plenty of good nymph patterns out there that are fairly close to the Western March Brown (Rithrogena morrisoni), but when the water becomes clear, the trout become quite selective. This fly has the shape, coloration and movement of the natural, and that can often make the difference between "troutless" and "troutful" days.
The fly also features inexpensive materials and is quite easy to tie, which is a redemptive quality when the tippet size drops to near invisibility, and flies snap off frequently. (Turkey, pheasant and other birds can be substituted if you don't have grouse.) The fly can also be tied with a gold beadhead.