
For finesse in shallow heavy grass, the best options here are the patterns that can be presented delicately and kept high or just under the film. Harrop's CDC Biot Emerger BWO - Solitude - Mayfly Dry Fly is a strong choice when trout are taking insects in the surface film. Harrop's CDC Biot Dun Trico - Solitude - Mayfly Dry Fly and Spotts’ Western Green Drake - Fulling Mill - Mayfly Dry Fly cover technical surface feeding with a realistic, finesse presentation.
If the fish are holding just below the grass edges, Mirror Mysis - Umpqua and Joe's Flies Trout Worms give you subtle subsurface options with a natural drift.
Switch to a streamer-style fly if trout are not eating on top and are reacting to movement instead of a dead drift. If the grass is too thick for a clean drift, move to a more open seam, deeper edge, or use a subsurface pattern with a controlled drift rather than a dry fly.
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