don't March Browns emerge on the river bottom and swim to the surface as adults? I always thought that was why there are so many wet fly patterns for MBs.
No, they don't.
The nymphs "let go" of the bottom and drift while swimming to the surface. This is where the wet fly shines.
Then, once in the surface film, they take a long time to transform (molt or emerge) into the dun.
"I would first recommend using a nymph dubbing. When you're talking about an emergence, the natural is half submerged under the water while it molts."
Not true for this species. The nymph lays in the film, struggling to get out of it's "shuck" and a "horizontal" type of emerger (or a dun) is the better choice.
A better style (more realistic) emerger for MB/GF is a TMC200RBL hook in 12/14 respectively, a nymph colored shuck and "abdomen" with light dun colored wing buds/wings and a creamy tan colored "thorax". I also like the effect of the partridge feather overwing. I add partridge legs to mine, but it really doesn't matter.
Having said that, many other flies and fly styles work, including sunken butt emergers and hi-floating catskill dries.
Just do yourself a favor and NOT try to fish it with 7x on a 3wt :lol: