The Green River is a stream with many faces. In it’s upper reaches in Wyoming, it’s a high plains river home to large brown trout. This is western ranchland country, and all through the summer trout hug the undercut banks in search of hoppers. That’s where you should be casting, with a Letort Hopper and maybe a Hare’s Ear dropper for good measure. The access isn’t great here, but there are places where visiting anglers can get on productive water for free.
Below Yankee Jim canyon, the Yellowstone settles into the character it will hold for another hundred miles or so. It flows through a beautiful valley (although you can see the beautiful Absaroka Mountains most of the time), and the river has a steady, but not rapid current. This is rainbow and brown trout water in the main, although cutthroat are pretty common as well. The water around Livingston is most famous, but the fishing is very good for many miles up and downstream from that popular western trout town. The trout fishing holds up all the way downstream to Billings in Eastern Montana. Below there, it is a massive prairie river home to pike, smallmouth bass, and catfish, but few trout.
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