I read online about these major mayfly and caddis hatches starting to happen on our freestones. So, I would think that the fish would be full of bugs in sizes 14 to 18. There are a few of them.
But, I’d say that 90% of what I’m finding are bugs in size 20 or smaller. Yesterday, I hit a local freestone for 90 min. Landed five trout and very many fallfish. They were full of small bugs.
So, I suggest having a bunch of size 20s on hand. I suggest a “tuft and tail” fly. In dark olive or olive-brown, it will mimic a small BWO emerger, of which there are plenty right now.
I’d also fish with a size 20 larva pattern, such as the Miracle Nymph. Tons of these bugs are in the drift all day long. A thread larva is very easy to tie yourself. Use dark olive or dark brown for the body. You can use thin wire or black thread for segmentation. That’s it.
Tie these flies as a dropper about 22″ above your anchor fly, such as a size 14 Frenchie, and you should be good to go. Ninety percent of my takes used to be on the anchor fly. Now, 50% of them are on the small dropper fly.
Size 20 flies seem to be a trout’s bread-and-butter food item these days. They don’t look sexy and won’t catch your eye in a fly shop. But, they certainly work on trout. These are flies that catch fish and don’t tend to catch anglers.