There is a week — never quite the same week twice — when the salmonflies crawl out of the Bitterroot and the whole river forgets its manners. These are not delicate insects. They are inch-and-a-half-long clumsy fliers, and when they fall to the water the biggest browns in the system abandon caution and feed in the open like there is no tomorrow. For seven days, give or take, the river fishes like a fairy tale.
The trick is timing, and timing the salmonflies is closer to weather forecasting than entomology. The hatch starts low and pushes upstream as the water warms, climbing the river a few miles a day. Get above the bugs and you fish to trout that have not seen them yet. Get below and you fish water that has already been gorged. Find the leading edge — the stretch where the first big bugs are just starting to crawl onto the willows — and you have found the week.
When it is on, fish a big, ugly, foam-bodied dry and do not be precious about your drift. The fish are looking up and they are not subtle. Slap it down. Twitch it. The takes are violent enough to break a tippet you tied lazily, so tie it well. This is not a hatch for finesse. It is a hatch for showing up prepared and holding on.
We track the leading edge daily during salmonfly season, and a guided float with Blackwater Ridge is mostly about putting you in the right two miles of river on the right afternoon. Miss it by a week and you have a nice float. Hit it and you have a story for the rest of your life.