Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.
Entoman on Sep 23, 2011September 23rd, 2011, 12:32 pm EDT
Most small freestones have surprising biodiversity as compared to larger rivers, tail waters, and especially spring creeks. Very few species (if any) necessarily constitute what we would refer to as fishable hatches, let alone be the cause for selectivity.
"It's not that I find fishing so important, it's just that I find all other endeavors of Man equally unimportant... And not nearly as much fun!" Robert Traver, Anatomy of a Fisherman