Spotted Sedge (tan caddis)

Telling it apart

• Tan to mottled-brown body and wings, size 14–16 — the classic "tan caddis."
• Long, thread-like antennae, like all caddisflies.
• On the water almost every evening from June to September, rather than in a narrow window like most hatches.
• The larva carries no case: it spins a fixed silk retreat and a capture net stretched across the current.
• Found clinging directly to rock and submerged woody debris, in stretches with steady current.

A net-spinning larva

Unlike the Grannom, which carries a square case, or the October Caddis, which builds one from bark, the Spotted Sedge larva stays put: it anchors a silk retreat to a rock and spins a net across the entrance that filters organic particles out of the passing current.

That dictates the habitat precisely: the net needs continuous, well-oxygenated flow to work, so look for it clinging to rock and woody debris in riffles and steady current seams — never in still water.

Summer's workhorse

Most hatches in this chapter run two to six weeks. The Spotted Sedge stays active for more than four months because the population doesn't emerge as one synchronized cohort — several overlapping generations keep insects available on the water every evening all summer.

In practice that means you never really have to guess whether "tonight is the night": a tan 14 caddis is justified on any summer evening, which makes it the most reliable default choice of the whole season.

Two sizes, one river

The Little Sister Sedge shares almost exactly the same habitat and schedule, just at a smaller scale. On the same seam it's not unusual to see both mixed together — which is why a trout refusing a repeated 14 will often take the very same pattern once it drops a size or two, with no need to change the fly itself.