I've thrown dozens of flies at trout on the Poudre, with varying degrees of success. There are a few, however, that I would consider to be staples for any angler to have on hand. Keep in mind that this is all based on my own trial and error - by no means is it intended to serve as a listing of magic bullets. Still, if you're going to fish the Poudre anytime soon, I'd have a healthy supply of each in your flybox.
1) Pheasant Tail Nymph: If I don't see a hatch, this is my go-to fly. I'm told the original created by Frank Sawyer was tied entirely from pheasant tail fibers, with no thread. Wow. Not quite that skilled myself, so I generally use an olive thread and a natural pheasant tail. I've also had much greater success on the Poudre with a bead-head variation, and have done particularly well with a red wire ribbing. The version you see here has a flashback tied with clear tinsel.
2. RS2: Still a bear for me to tie, but this little bug works great on rainy summer days when the fish are actively feeding, but sucking flies out of the film. I tie them in size 20-22, which seems to be a good match for emergers on the Poudre. They're also small enough to work well during most midge hatches, and I like to use them as a trailing fly behind a caddis on the surface.
3. BWO Mayfly: Your flybox for the Poudre should include dozens of this pattern in sizes 18-22, as it's a standard hatch in the early spring and continues to fish well throughout the summer. The real pros will tie in CDC puffs for the wings, but hackle tips work just fine, and I think they're easier to tie in.
4. PMD Mayfly: I like to have a healthy supply of these on hand because they're a close match to the typical BWO, but they come in handy during certain times of day when visibility is at a premium. I like to tie this one with a cream-colored thread and white hackle and wings.
5. Elk Hair Caddis: This one's pretty much a no-brainer, particularly on the lower Poudre. It's been particularly deadly for me during post-runoff summer days in August and September, when the caddis hatches tend to be thick. Be sure to stock your boxes with plenty in sizes 16-20. I like to tie in some white or orange hi-vis, an easy modification that doesn't change the fish-eye view of the fly but eases the strain on the angler's eyes.
