A freestone Summer staple in many Western US streams, the PMD is so available that one should take the time to tie up nymphs, emergers, duns and perhaps spinners. The PMD nymph is a blocky clinger that I think is easily matched by GRHE’s or a pudgy PTN. Sizes 14 to 16 are usually appropriate. Like the Callibaetis, the PMD gets progressively smaller as the season advances. Start larger (14) in June and tie on smaller (16) as you move through July into August. The nymphs are going to be in faster currents and subject drifting. Fishing the nymph alone or as a dropper is the norm. I have used the general purpose Gold Ribbed Hare’s Ear and a Copper John. The emerger pattern is so enjoyable to fish that I would experiment with all the regulars (Klinkhammers, Quigleys, or an in the film unweighted nymph). The dun pattern has been for me a tannish/cream dun, either a parachute or standard dry with a dun colored wing. I mention spinners because they are do fall in the evening and a few are always a good idea. I know this because I am often without them and hence unprepared (I have had this problem with Callibaetis spinners as well). I am by no means an expert re mayflies and only know what I do from observations and studying Westfly, Troutnut, Worleybuggerflyco. I do know that they are necessary on Western US rivers.
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