Consistent and somewhat higher that normal flows in Fall River Basin streams ( Bechler and Fall Rivers, Boundary, Mountain Ash and Proposition Creeks) means that good fishing should result here for the rest of the Yellowstone Park fishing season. Other than AM trico activity (seems to turn off, like on command, just about noon), some speckled duns and later a few mahoganies blown in from faster waster below are what remains of the extensive late June-early July mayfly activity. Now until killing frosts arrive, is the time to concentrate on presenting terrestrial insect patterns. Doing so will seem obvious to the fly-fisher that ventures through meadows to reach water. Presenting these patterns in the proper manner is more important than pattern selection. That means presenting to the far bank or downstream, both through a slow drift. For sure, you will not experience crowding and early season mosquitoes swarms are much diminished. Deer and horseflies, however, reign supreme, so dress accordingly.