Yellowstone Park

If you prefer dry flies, terrestrial patterns are the way to go almost everywhere on Park streams. We tend to overlook ant and beetle patterns compared to those of hoppers. But a delicately placed ant or beetle can be very effective along banks and overhangs not in direct light.
Fly Patterns to use:
Bionic Ant 2.0 Brown
CDC Biot Rusty Spinner
Pheasant Tail Flashback