Little Black stones and green caddis larvae for freestones. Lots of patterns, but I go simpler and less flashy in winter. I start with #12 and step down to #16 and #18 if I'm not getting hits. My basic LBS nymph is a few black hen fibers for a tail, black tapestry wool for body and thorax, grey antron for wingcase, and black hen hackle. Tie in tail and yarn. Wind yarn up about half way in thin abdomen. Tie in wingcase facing back. Wind slightly thicker thorax. Tie down and cut off yarn, wind a couple of turns of black hackle, pull wingcase forward, tie off and finish fly. This was my go to winter nymph for years.
Eggs and worms are staples too. I used to be more a chamois worm guy, but now more often use a micro Chenille worm in pink tied at the head, not the middle. Sucker spawn is a good one. Small McFly foam glo bugs are great in 14 and 16. See Tim Flager video.
Used to use gray and cream honey bugs too; Walt's worm and simple muskrat fur nymphs will do.
Midges; I mostly fish limestoners in winter now where midges are the bread and butter. Lot's of options but simple pupa in dark colors, top secret midges, and miracle midges probably see more duty than most. Zebra midges are great, but use them less where I go. My basic zebra midge for freestones is silver bead, black thread body, small silver wire rib in 16 to 20. Used to use one in 22 with a CDC or antron wing in highly fished spots. Now I just bring my limestone midge box (with mostly 22 and 24) everywhere and fish smaller midges.
Streamers are great in winter. I like subtle colored jig streamers with pine squirrel strips or craft fur wings. Olive, black, white are my basic colors. Fish slow and strike at lightest weight on the line - most times they don't hit hard in winter. Of course buggers in same colors work.
This is what I do. I don't have any arguments with the choices above. Jiggly Pat's stonefly and others were hot in the fall - can't imagine they wouldn't work in winter. Don't need many flies - best ones are the ones you have faith in.
