Photo by Chuck Robbins.

For the Western fly-rodder, caddis-flies -- and the splashy rises of trout plucking them from the surface -- define summer. While this bonanza offers some of the best dry-fly action of the year, most caddisflies never complete their life cycle to become a tent-winged adult insect. They get eaten by trout before they ever reach the surface, much less spread their wings and do their mating dance.

Their order, Trichoptera, represents the most diverse species of insects that are exclusively aquatic in their larval stage. There are thousands of individual species of caddis-flies, and trout fishermen need to know a few things about them.

I spent 10 years guiding summertime anglers on some of the West's finest caddisfly rivers. I learned most of these patterns and techniques from gents who'd been at it much longer than I had, and made a few innovations of my own. Add these techniques and patterns to your repertoire and enjoy a better summer of fishing.

A BUG'S LIFE
Caddisflies have a life cycle of three stages: larva, pupa and adult. They're different than say, stoneflies, whose larvae hatch directly into adult insects. Take the time to look at the caddis' life cycle and see how trout feed on them during each individual stage, and you'll hook more trout this summer.

1) Larva
All caddis fly larvae are capable of spinning silk. But how they use this silk is what separates them and dictates their appearance. The three varieties of caddis larvae are:

• Cased-caddis,

• Net-spinning caddis, and

• Free-living caddis. This last category, the free-living, is of little concern to any stream fisherman because they primarily exist in lakes, and even then, are largely unavailable to trout.

Cased-caddis create a case around their fragile bodies, using silk and stream-borne debris. By rolling rocks, you can find their cases -- generally about a half-inch long and looking like a conical tube of sand and twigs.

When a larva is undisturbed, it will generally poke its head out of the case and become visible.

Cased-caddis larvae often become dislodged in the currents of swift riffles. When trout find them, they eat them -- case and all.

Imitating a cased-caddis larva is very simple, and a Zug Bug or Prince Nymph can pass as one. But a more specific fly that I prefer is a Beadhead Cased-Caddis.

(For examples of the patterns discussed in this article, check your local fly shop, or visit www.idylwilde.com, or www.umpqua.com.)

Fish your cased-caddis imitation the way you would a dead-drifted nymph. Use a strike indicator and enough split shot to keep it bouncing along the bottom.

Target swift riffles and the current breaks below them. That's where opportunistic trout will lie in wait.

I often fish this pattern as a dropper on a tandem rig with a stonefly nymph above it. The larger stonefly nymph keeps the caddis larva in the zone and also draws the attention of fish -- which may then opt for the smaller caddis pattern.

Net-spinning caddis don't build a case. They construct a rough shelter of gravel and debris that they attach to the sides of rocks, similar to a lean-to. Then they spin a net, much like a spider's web, to trap their food.