The Western Green Drake is one of the largest mayflys and a favorite summer hatch on the Big Wood and Henry’s Fork. On the Big Wood River they typically hatch in early July, but on low water years the hatch window moves up to late June and on high water years (like this one) the hatch gets pushed out until mid-July.

Green Drakes belong to the “clinger family” and like faster water than most mayflies—check out the robust legs on the Green Drake nymph shown in the photo! Green Drakes are unusual for mayflys in that instead of emerging from their nymphal shuck at the surface they crawl out of their shucks on the bottom of the river then swim “naked” to the surface. Although the nymphs live in fast water, they migrate to slower edges to emerge, so make sure to drift your dry fly down the slower secondary seams next to the fast water runs.

It takes Green Drakes time to dry their big wings and fly away and I find emergers fish well. My favorite fly pattern for the Green Drake hatch is Scott Sanchez’s Parachute Midge Emerger. I also have good luck with a dropper of an unweighted peacock soft hackle pattern, which imitates the “naked” Green Drake adult swimming to the surface. Before the hatch, a Prince Nymph is a good bet--I think the white goose biot wings are a good imitation of the nymphal case splitting open.

PME Green Drake

• Hook: #10 TMC 100

• Thread: Olive 8/0 Uni-thread

• Body: Peacock Ice Dub

• Rib: Krystal Flash

• Wing: Dark Grey Parapost

• Hackle: Brown (or Grizzly) Hackle

For more information on the Green Drake Hatch on Henry's Fork, see this Fly Fisherman article and listen to this Podcast with Mike Lawson.