Because it has the right water chemistry, the Deschutes is rich with insect life. Because the aquatic terrain varies tremendously, from riffles to runs to flat-out, grip-your-seat rapids, the Deschutes hosts a wide variety of insects, from minuscule midges to giant, blundering stoneflies.

The river is most crowded with anglers during the salmonfly crazies, from mid-May to mid-June, when a massive hatch of giant salmonflies and golden stoneflies sparks a trout feeding frenzy. Trout gobble the nymphs crawling towards shore (these insects hatch on rocks or trees at water level), gulp adults that fall from the vegetation overhanging the river, and cannonball skittering egg-layers that can't regain the sky.

From mid-June through August, caddis hatches are dense, and at times, hatching mayflies will bring trout to the surface as well. Fishing may be good all day during June and into July, but as temperatures climb to 100 degrees and beyond, hatches are compressed into the last few minutes of daylight. Your best chance of dry-fly fishing on days like this is to work a grasshopper along a wind-swept, grassy bank during the afternoon, and find some shaded canyon water in the evening. If you are lucky enough to encounter cool, wet weather during the summer, bugs of all types may burst from their nymphal habitat, causing trout to gorge.

When there are no hatches, or no rising fish, you can always fish nymphs and streamers, and if you work at it, find success. Effective nymphs include the Serendipity and Deep Sparkle Pupa in tan, brown, and especially bright green, #14-18; Pheasant Tail Nymph and Gold-ribbed Hare's Ear #12-18; and big (#6-8) stonefly nymphs like the Kaufmann stonefly in both black and gold.

The stonefly hatches of mid-May and early June provide the first good dry-fly fishing of the year. Concentrate your fishing near bankside brush and rocks where the bugs split their nymphal husks and emerge as fully-formed adults.

It's important that the nymphs be heavily weighted, or else add extra split-shot to get the pattern to the bottom. Bead-head nymphs are great on the Deschutes.

As with most trout rivers in the fall, trout feed most consistently on #18-#20 caddis and mayflies because that's what's available. In some areas, trout will snack on Mahogany Duns, which hatch sporadically. Sometimes a midge hatch may be the prime dining item. With the exception of the Mahogany Dun and the October caddis, fall insects are scaled down.

Despite its name, you might encounter the October caddis in late September, though you'll rarely rendezvous with a thick hatch. From a guide and one other angler, I've heard of intense hatches that offered some wild fishing; however, in all the years I've fished the Deschutes, I've never encountered it--you're more likely to see a few in the air and in the bushes. Since trout see them daily, they'll nail them when they get a chance. Alternatively, in heavily fished areas, trout see bulky caddis imitations every day and learn to shun them; you'll do better with a small caddis or mayfly imitation.