Maccaffertium vicarium or the March Brown mayfly is a major hatch throughout the U.S. In the East and Midwest this hatch usually occurs from early May into late June. Formerly known as stenonema vicarium, this bug is rather slow to emerge from its nymphal state making soft hackle emergers, cripples and low riding comparaduns very effective fly patterns. See also; spinner and March Brown Set. Tied on a Daiichi 1560 barbed, or a Tiemco 3761SPBL barbless, chemically sharpened nymph hook.
