The single biggest mistake anglers visiting the Yellowstone area for the first time is simple, and probably surprising: they fail to bring a rod heavier than a nine-foot five-weight.
It might come as a surprise that this qualifies as a “mistake.” After all, five-weight rods are the reigning king of fly rods, the usual “do it all” rod suggested to rookies and experts alike. In a lot of the country, they probably are the right choice for a one-rod quiver. Around here, they’re not.
I’d like to say it’s because our fish are so big, but that’s seldom the case. The situations in which giant trout (or other fish) are a big part of why heavy rods make sense are the following: you’re chasing fall-run brown trout, you’re after carp on the Missouri River, or you’re fishing the “Land of the Giants” stretch of the Missouri River for big rainbows in the spring. That’s it.
Otherwise, these are the reasons to go heavier, all of which reinforce one another:
1.) Big, heavy, wind-resistant flies
Simply put, our flies are often bulky enough to cast that a stiffer rod than even a fast-action broomstick of a five is helpful. Fives are going to struggle with the latest articulated streamers, of course, which are bugs that many visitors aren’t going to fish anyway, but they also struggle with some of the “standards” we use all summers: large hoppers, Chubby Chernobyls, and Salmonflies. Notice that these are all dry flies. Where these bugs are concerned, it’s the wind resistance that counts, rather than their mass. A five-weight in the hands of a skilled caster can usually handle even large nymphs, since they punch through the air with greater ease than fluffier flies.
2.) On the other hand, a stiffer and longer rod than your average five-weight really helps when nymph rigs get complicated
The average five will struggle when you tie on a big stonefly, another nymph, a couple split shot, and a giant indicator. In particular a five-weight may require more time and power to lift this rig from the water than a heavier rod. This hurts casting as well as hook-setting.
Wind is ever-present around here, particularly on large float rivers like the Yellowstone, Missouri, and Madison. When the wind is blowing right in your teeth, or even at your back, having a rod with some muscle is exceptionally helpful in getting good turnover on your casts. Good turnover means good accuracy, fewer tangles, and less “forcing it” into the wind, all of which makes for a more-efficient day of fishing.
So which rod do I suggest, then?
By far my favorite “do-it-all” rod around here is a nine-foot six-weight, particularly a relatively fast-action model (though not a true saltwater thunderstick) using a line rated a half-size heavier than the AFFTA standard. If you don’t know what that means, don’t worry about it. Just ask for a contemporary general purpose trout line and that’s probably what the fly shop guy will sell you.
In essence, this rod and line combo (reels matter less) is a “6.5-weight.” This makes it heavy enough to cast big streamers, fight big fish, punch wind-resistant dry flies into a gale (assuming you’ve practiced casting lately), and pick up big, dirty nymph rigs. This rod is also still light enough to fish all sizes of dry flies with all but the lightest tippets, to cast without too much fatigue in a day of fishing, and to land the cast softly and accurately enough save on the gentlest, clearest streams like the Paradise Valley spring creeks and various meadow streams in Yellowstone Park.
What should you use on such gentle streams? Why, your nine-foot five-weight (or four-weight) of course! I never said you shouldn’t use a lighter rod, just that it shouldn’t be your heaviest rod available.