The name “sulphur” (or “sulfur”) is attached to several mayfly species in the genus Ephemerella. The “big sulphurs” of the East are usually E. invaria (also called the “light Hendrickson”), and its smaller cousin is E. dorothea dorothea, the pale evening dun. There are other species, even from other genera, also called “sulphurs” locally, and frankly it doesn’t really matter. If there are yellowish mayflies emerging, a Sulphur pattern will usually catch them.
The nymphs of both E. invaria and E. dorothea dorothea are “spiny crawlers,” which means they don’t swim all that well. So when it’s time to emerge, their rise to the surface creates a smorgasbord for trout. That’s why emerger patterns like the one shown here are so effective. Once the duns are on the surface, fish an emerger pattern as a dropper off a dun pattern to exploit both stages and figure out which one the trout are keying on.
As usual, this video from Tightline Productions offers crystal-clear instructions for tying this elegant pattern by author and blogger Matt Grobert. The way Grobert combines different kinds of thread and uses a “dubbing noodle” to veil the abdomen are brilliant techniques that can be adapted to many other patterns. The finished fly is a great imitation of an emerging sulphur, plus it offers enough flotation to stay right at the surface.
Matt’s Sulphur Emerger
Hook: 2X-short emerger hook (e.g. Dai-Riki #125), sizes 14 and 16.
First Thread: Yellow Danville Monocord, 3/0.
Shuck: Mayfly-brown Zelon.
Dubbing noodle: 8- to 10-inch piece of Brown Danville, 6/0.
Underbody: Yellow Danville Monocord, 3/0.
Second Thread: Olive Danville, 6/0.
Abdomen: Brown Australian possum.
Thorax: Pale yellow rabbit fur.
Wing: Fine caribou hair, cleaned and stacked.
Head: Olive tying thread.