Long Horn Sedges
.............................Fly Fishing Yellowstone National Park

Long-Horned Sedges (Oecetis species) - Larvae, Pupae and Adults

The Long-Horned Sedge is a tube case maker that crawls around on the bottom of the
stream searching for food.

We have not tried an imitation of the larvae simply because during the time they would
probably be most effective, we felt there were better options at Yellowstone. Since we
haven't tried it, this is strictly a guess.

Trout probably eat more of the hatching pupae than they do anything. At least they are
readily available to the trout when they try to reach the surface of the water to hatch.
They do hatch mid-stream but usually in the calmer areas of water such as pockets or
the heads and tails of pools. In the slower, smooth flowing streams, they may hatch

The pupa may be imitated with an emerger pattern fished near the bottom; with a wet fly
that appears to be swimming to the surface; or with an emerger pattern fished dead drift
just beneath the surface. We prefer a wet fly imitation. Fish it on the swing, down and
across and allow it to reach the surface when it is directly downstream. You do this by
stopping the drift and slowly raising the tip of the rod. The idea is to imitate the pupa
attempting to reach the surface to hatch.

The females deposit their eggs by dipping down and at least sometimes touching the
surface of the water. We believe some of the eggs are dropped from a few inches
above the water. This usually happen very late in the afternoon and early evenings.

Dead drifting an adult pattern or a spent pattern usually provides good results. In the
smooth, slower flowing streams, we use a down and across presentation to individual
trout. In the pocket water or faster flowing streams we usually stick with an up or up and
across presentation.

Coming Up Next:
Long-Horned Sedge - Fly Pattern Colors

Copyright 2008 James