Species Insects & ArthropodsGrannom

Grannom

Brachycentrus americanus

CommonInsect & Arthropod
Illustration of Grannom (Brachycentrus americanus)

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.

Habitat
Clean, cool trout streams with moderate current
Diet
Larvae: algae and fine organic particles filtered from current. Adults: water
How common
Common

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