Whether you float the Teton River, walk in to the Blackfoot River on the Wildlife Management area or try streams of equivalent character, terrestrial insect patterns are your best bet for action this time of year. In Teton River canyon chernobyl types work well, and on the Blackfoot River with its slower flowing waters, traditional hopper patterns would be best. Some of the smaller streams now at base levels (Robinson Creek) or having significant diversion for irrigation (Fall River) are warm, and action on them can slow. There are some good exceptions to this warming. Birch Creek (try attractor and terrestrial patterns) in the family area stays cools because of springs above and within the area. Warm River (try attractor, PMD life cycle, sally, and terrestrial patterns) below the spring will remain good fishing to the end of the season because the spring provides cool water in abundance. The same happens with Palisades Creek (Try flav, terrestrial and attractor patterns) which receives cooler water from subsurface flows from the upper lake. The lower lake also has an subsurface component to flow coming out. Both these keep Palisades Creek water temps at best levels for trout and insect activity.