WD 50

The WD 50, designed by Carl "Boomer" Stout, is an innovative Baetis nymph pattern that evolved from Stout's tinkering with the iconic WD-40, created by Mark Engler. Acknowledging the Green River's legendary Baetis hatches, Boomer modified the original design, adding an emerging wing case made from duck flank feathers (such as Wigeon) to mimic the natural transition of the Baetis nymphs. The addition of a flashback and a chunky, dark thorax was a game changer, significantly increasing the fly’s attraction and triggering more strikes from fish. Boomer found that this fly was particularly effective during the first hour of the Baetis hatch, which led to the WD 50 gaining widespread acclaim

Fish Early in the Hatch: The WD 50 excels during the first hour of the Baetis hatch, when nymphs are actively emerging. Cast the fly just below the surface or in the water column, and focus on the early part of the hatch when fish are most likely to take advantage of the abundant nymphs in the water.