The Grannom is a caddisfly famous for its spectacular spring emergence on trout streams, when thousands of dark, four-winged adults fill the air and female clusters of green egg masses bob in the current. The larva builds a square, four-sided log-cabin case of plant material perfectly camouflaged among streamside debris. The grannom hatch is one of the most anticipated events in eastern fly-fishing.
Not certain it is a Grannom? What bug is this? walks through what to check first and the lookalikes that catch people out.
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