Below is a URL for an article on fishing midge imitations, it was written for Montana waters but I found it applies very well to Putah, hopefully I'll have a chance to try a few new things this weekend though it looks like the flows will be driving a change in tactics. Midges have been a bit of a mystery to me, the article covers a lot of ground that takes out the mystery, including size, color, life cycle, presentations, and other tips. The article isn't short, but it's well written and comprehensive, thought that there may be a few others out there with some of the same questions I had. My last two outings have only seen one fish to net but the ones that got away have made me a believer in the power of tiny flies.
Good article. I believe it does a good job of giving an entomological background on midges and their relevance to our sport. I don't remember off the top of my head, but midges are fairly common in lakes as well...and important there as well.
I have caught lots of fish on midges--lots of big fish. They are definitely important. I used to be sort of skeptical toward the use of midge imitations. They just seemed too small to make much of a difference. Man, was I wrong. The fish eat them year round. Check every rock in the creek. When you pull out a gob of moss while dredging a run with a nymph, check out the moss for insects. You'll more often than not see midge larvae. THey're everywhere. I have caught fish on midges in the middle of a BWO hatch, even during a caddis hatch. They're that important.
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"Nothing makes a fish bigger than almost being caught."