PMD’s have been coming off in full force on the Spring Creeks. Mornings have been slower, but the afternoons have offered dry fly anglers some solid action. From what we can gather, the larger (size 14-18) infrequens PMDs hatched at bit earlier on the Yellowstone Aquife, which flows through Armstrong’s and DePuy’s and a day or two later on Alluvial Fan Aquifer, which flows through Nelson’s. It took the fish a day or so get really get on the bugs but they are keyed in now. We’ve heard reports of some smaller (size 16-20) inermis PMD’s coming off on Armstrong’s and DePuy’s as well, which shouldn’t be far behind on Nelson’s.
If you get to the creek early you might try nymphing with scuds, midge larva, and PMD nymphs. If the evening before was relatively calm, you should also look for spent spinners from the night before. Sometimes these will get stuck in an eddy and the fish will be looking for them early in the morning. Depending on the day, around 10:00 or 11:00 you should start to see some surface activity. A sparkle dun or something similar with a trailing shuck is a good choice when you first notice duns coming off. After a while, you might switch to a compara dun or no hackle. Fish with 6X or 6.6X to get the best drift…
