5 Best Flies for Trout in Montana

If you could only carry one dry fly into Montana, the Elk Hair Caddis would be the argument. Caddisflies are the dominant surface insect on most Montana rivers, and Al Troth's classic pattern imitates emerging and adult caddis convincingly enough that trout rarely second-guess it.

It's buoyant, visible, and durable - everything you want when you're working fast riffle water or fishing long summer evenings when caddis are dancing off the surface in clouds. Tan in #14–16 covers most situations; drop to #18 on spring-creek water where fish get selective.

The Parachute Adams is the universal mayfly - a searching pattern that suggests enough different species that trout take it when nothing specific is happening. On Montana's rivers it doubles as an imitation for Pale Morning Duns, Blue-Winged Olives, and a dozen other mayflies depending on the size you fish.

The parachute post makes it visible in broken water and gives it a low-riding silhouette that produces well on flat, technical water where trout can inspect a fly carefully.

Nymph fishing accounts for the majority of trout caught in Montana - fish spend most of their feeding time subsurface - and the Pheasant Tail Nymph is the subsurface equivalent of the Elk Hair Caddis: always worth having on the bottom of a two-fly rig.

The bead-head version gets down quickly in Montana's heavy runs and riffles. It imitates countless mayfly nymphs, particularly Baetis (BWO) nymphs that are present year-round in virtually every Montana river.

The Woolly Bugger is Montana's big-fish fly. When you want to move a 20-inch brown out from under a cutbank, nothing does it quite like a #6 olive Bugger stripped with authority through the deep water. It imitates everything from sculpin and crayfish to large stonefly nymphs and leeches.

On rivers like the Big Hole and Bitterroot, streamers fished from a drifting boat produce the largest fish of the day. A weighted Woolly Bugger is the foundational streamer before moving to more specialized patterns.

Nothing in Montana fly fishing compares to the Salmonfly hatch. When these massive stoneflies - some as large as your thumb - blanket the river surface in late May and June, even the biggest, most selective browns throw caution aside. A large orange Stimulator in #4–6 is the go-to imitation during this window.

Outside of the Salmonfly hatch, the Stimulator in smaller sizes (#8–10, yellow) imitates Golden Stoneflies throughout June and July. It also works as a general searching dry on pocket water when you want a fly that's highly visible and floats through technical currents.