Midges
Midge patterns are a must in Colorado. They can out produce any bug in your box. The only subsurface fly that can reliably catch fish year round. Don't fool yourself into thinking that the fish won't see these tiny offerings. A good look at your seine will reveal larvae that make these look like giants. Midge patterns are probably the most varied of all freshwater flies. You can drive yourself bonkers looking through all the midges at the local fly shop; for every fly, there is at least five more that vary only slightly. Here are a few that you should definitely not leave home without.
Disco Midge Palomino Midge Beadhead Peacock Midge
*Pearl or red Crystal Flash *Black, Brown, Grey, Olive *Silver bead head
Black Beauty Brassie Bloodworm
*No jewel head, silver rib *Bead head instead of herl * Red thread Rib
Griffith's Gnat