Although this post will be entirely subjective, I’m hoping — as a native to the state of Colorado as well as an unrepentant fly junkie — to identify the 25 best dry flies for Colorado fly fishing.

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Why You Need a Well-Stocked Fly Box

The following scene is brought to you courtesy of a well-stocked fly box, painstakingly created at the hands (and wallet) of a confessed fly junkie, one altogether motivated by FONH — Fear of Not Having… the right fly at the right time.

I’m standing precariously and nearly hip-deep in the black and swirling current of a gorgeous yet powerful Colorado mountain river. My rod, tucked under my arm, seems, at its tip, inexorably drawn to want to take a peek under the surface, as if to scout and report back to me about the goings-on of my finned targets. My back aches and my eyes strain; I’ve asked a lot of them today.

My feet are cold. I’m hungry. I have to pee.

My fly box, the black, rectangular one — one of about six I carry at any one time — is open. I gaze at it its innards intently. I’ve studied its contents a thousand times. A thousand and one now. I know its inhabitants well. Some of its tenants have been there awhile; the grizzled vets, as it were. Rows and rows of them. They’re ragged. Some sport rusted hooks. Some still have flecks of dried trout goo clinging to their hackles.

And then there are the freshies. I added them over coffee and a slice of bacon a few hours ago. They are the young bucks, the flavor-of-the-month, born of the recommendation from the local fly shop guy just yesterday. I’m the sucker he saw coming, just as soon as I came into the shop and made a bee-line to the fly case.

They occupy once vacant slots. I want to give them a try, but, after all, the vets have served me well over the years. I’m indecisive. Hung up. Second guessing. I take a deep breath, stretch my neck, and take a quick look up river. My fishing partner, probably my son or another old fishin’ buddy, is making his way to the next run, out of earshot and, thus, is useless to me. I’m offline, so to speak. I’ve just clipped an unproductive fly away from my tippet and am hoping my next setup will be The One.

Right then, something catches my eye. A large flying insect rises, angelically, past the brim of my cap, hovering like Tinker Bell just off my right shoulder. And then I spy another. And another. And yet another. Soon the sky is full of them and the water below them, ahead of me, is boiling with feeding trout. It’s a Green Drake hatch and they’re feasting! Legendary. Mysterious. Unpredictable… Thrilling. And my choice is made.

Hands shaking with excitement, I can barely get one out of my box and tied on, but, within seconds, I’m false casting, drying my dressed Drake — an imitation I haven’t had the opportunity to use in years — while eyeballing the activity in the run ahead. The only problem will be whether or not a frenzied trout will take my offering among the cornucopia of naturals now drying their wings on the water. I manage to land the beefy mayfly imitation within a few inches of where I aimed it and, within a millisecond, I’m rewarded with a thrashing strike.

I confess, this scene is a fictitious amalgam of my imagination combined with similar episodes that have actually played out several times in my fly fishing life. The moral of the story is clear: when it comes to fly selection, you can never have too many choices.

But, you ask, how can one — especially one new to the game — be as prepared as possible for the myriad of potential Colorado insect hatches on any given day, in any of a number of different places, times, and conditions? Answer: by building your fly box with these essential Western U.S. fly patterns as the foundation of your well-stocked fly box(es).

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1. Parachute Adams

When it comes to dry flies, I can say, without hesitation, that I’ve caught more Colorado mountain trout with a Parachute Adams than any other fly. I suppose that’s because it serves as a highly versatile imitation for many of the common aquatic-born flies one will find floating down Colorado streams and rivers. What I like most about it, aside from the fact that trout love to eat them, is that it’s usually-white parachute post is easy to see.

You can get them with brightly colored posts as well, but I tend to stick with white. Start your collection with several PAs of differing sizes, from 14s to 18s. By the way, don’t fall into the trap of thinking a bigger fly will automatically be more attractive to a fish. More often than not, Colorado fly hatches are made up of smaller sized insects. If you have a few Adams in the most common sizes, you can let what you see in the air or on the water determine which size to select from your box.

2. Elk Hair Caddis

A fly junkie? Yes. An out-and-out expert on Colorado entomology? No. That said, I can say with a high degree of confidence that the Caddisfly is among the most frequently encountered flies on most Colorado trout streams and rivers. Often mistaken for a small moth, the adult Caddis has a very distinct shape and wing-style that is best imitated by the Elk Hair Caddis. If there’s a Colorado fly shop that doesn’t stock tons of Caddis in a huge variety of styles, sizes and body colors, I am not aware of it. It would go out of business anyway, so it’s a moot point.

A good fly box will stock a few basic patterns in size ranges from 14s to 18s. Stick to the basics at first: olive body, tan body, dark body, with the standard elk hair hackle. Caddis are sturdy, high-floating, highly visible flies that you’ll probably use over and over again. Incidentally, if you become a steady fly fishing angler, it’ll only be a matter of time before you experience a Caddis blizzard. The most legendary of these is the world-renowned Arkansas River Mother’s Day Caddis Hatch, which rolls in waves, up river from about Pueblo to Leadville, every year, right around…you guessed it, Mother’s Day.

3. Blue-winged Olive

They spared no expense on the naming of this fly, although most anglers simply refer to this fly as a BWO. The adult version of this fly features an olive-colored body and a pale blue (nearly gray) wing. Again, because BWOs (baetis) hatch throughout the day and throughout the year, they are among the most frequently seen flies on Colorado waters. I confess that, while I have a solid stock of these in my fly boxes, my aging eyes have a harder time seeing these on the water, so I’ll often opt for a Parachute Adams in place of a BWO. Stock sizes 14s to 20s in these too.

4. Pale Morning Dun

Also known in common angler parlance as PMDs, these flies mimic lighter colored mayflies (comparadun) and, despite their name, these flies hatch throughout the day. Typically featuring a yellow toned body and a grayish hackle, PMDs are a little easier to see, however, trout tend to be very selective with PMDs, so stock sizes 14 to 20 and vary the color scheme from darker versions to lighter versions and don’t hesitate to change switch them out until you find the variation they like.

5. Green Drake

In my experience, a Green Drake hatch is a rare and delightful occurrence. Since Drake hatches tend to happen in mid July through early September, they are not an imitation you will often use. Once described to me as the T-bone steak of mayflies, the Green Drake is the most commonly seen variety of Drakes in Colorado. You might see them in gray or brown, but the green version is my go-to.

Green Drakes feature a green, extended body (often curving upward) to a delicately extended tail. The adult patterns typically feature a pronounced vertical set of darker gray wings. When a Green Drake hatch is on, trout get myopic and stupid, however, Drake hatches don’t tend to last long, so if you see them start to rise off the water, try not to wet yourself from excitement, and act quickly. Fly shops stock Drakes in larger sizes. You should too. Build your box to house at least a row of them from size 10 to 14.

6. Yellow Sally

Known as an attractor pattern, Yellow Sallies usually feature a bright yellow hackle along with a bright yellow body with a tiny red tip right at the hook shank. Attractor patterns, like Yellow Sallies, in the words of Jackie Gleason as Sheriff Buford T. Justice in the Smokey and the Bandit movies, are an “attention getter.” I honestly think when trout see an attractor fly pattern on the water, they get briefly mesmerized into either an angry or a just plain stupid strike.

For me, Yellow Sallies have been most productive in Summer and Fall in a meadow stream setting, late in the day, when things have gotten a little slow and you need to shake things up. That said, they’ve also drawn fire on larger rivers just as the sun tucks behind a cloud or behind the mountainous horizon. Stock a few Sallies in sizes 14 to 18.

7. Ginger Quill (Quill Gordon)

As a kid, my dad would always stock our fly wallets with a few “Ginger Quills.” This early season mayfly imitation is a variation of the Quill Gordon, featuring a ginger-colored body and mottled wing pattern. If you ask your local fly shop to direct you to the Ginger Quills, they’ll look at you with the reverence only afforded grizzled vets (or senile codgers) and point you to Quill Gordons. Just select a few in the ginger tones between sizes 14 to 18 and you’ll be good to go when you see these mayflies start to rise off the water. By the way, in their natural setting, Ginger Quills are unusually beautiful mayflies. When backlit by a setting sun, their color gives them a reddish-orange aura that is both lovely and a dead giveaway that GQs are on the hatch.

8. Humpy

Found in several different colors, Humpies are a particularly effective attractor pattern, especially in a wide open Summer meadow setting, where a million different insects can be seen flying, crawling and hopping about. The Yellow Humpy is probably the most commonly used Humpy pattern in Colorado.

Not what you’d call elegant, the Humpy looks like a VW Bug with wings, but in the right conditions and settings, when trout see it hit the surface above them, they often lose their senses and hammer it with a determined attack. Since, with a fair amount of hackle-heft, they tend to sit high and badass on the water, they make a good fly from which to trail a smaller nymph “dropper.” I don’t have any little Humpies in my boxes. Go with a selection of 12s and 14s and feel free to mix in some other colors besides yellow. I’ve had a decent amount of success with green ones too.

9. Trico (Dun)

Let’s talk Tricos!

Tricos should be a staple in every self-respecting fly box. Tricos are a frequently occurring fly in quite a few areas of the world. Simple patterns, Tricos lean small and typically feature a black body with a set of white wings.

The adult (dun) pattern is easily identified by a vertical wing set or with a parachute post. Since they tend to run small, it can be helpful to have a few with brightly colored parachutes. Even the white parachuted ones can be difficult for the aging eye to see. When Tricos hatch, it’s an epic thing to behold, however, when they do, they tend to blanket the water with naturals, making it challenging to draw a strike on your imitation when the fish you’re hunting have so many other options. On the other hand, if you’re lucky enough to get hot during a Trico hatch, make sure your camera is easily accessible.

10. Trico (Spinner)

As described above, the Trico Spinner pattern is nearly the same as the adult version but with one very distinct difference: a flat, splayed-out wing posture.

While duns mimic an emerging fly drying its wings on the surface before flying up into an overhanging willow to mate, spinners mimic the post-mating version, or flies that have completed their procreational business and have now fallen back into the water to live out the waning moments of their lives. If they had tiny little cigarettes, this is when they’d be smoking ‘em, but this is also when they become the equivalent of those weird food-flecks you’d feed a pet goldfish. Stock Trico Dun and Spinner patterns in 18s to 22s and get ready for a little eye strain. That said, when a Trico hatch ignites, you may want to smoke a cigarette afterward too.

11. Griffith’s Gnat

The Griffith’s Gnat may rank as one of the most underrated flies every fly box should contain. Again, not the most elegant imitation you’ll see, but this fly, when drifted correctly in the right situation — think long, slow runs when tiny black midges are buzzing close to the surface, while not much else appears to be — will bring trout up from the depths to sip what I’ve heard looks to them like an amorously locked cluster of yummy black gnats. Why eat one piece of popcorn when you can eat a whole popcorn ball, right? We recommend stocking a couple in every size from 14s to 22s. Griffith’s Gnats typically fish better on lighter tippet, and can be fished dry or allowed to sink into the surface film a little.

12. Damselfly

For some unknown and unsubstantiated reason, I didn’t used to think that trout really liked Damselflies. I thought that right up until the time I saw a lake trout absolutely annihilate one I happened to be watching flit along the bank of the pond I was fishing.

Big, beautiful, blue, minding-its-own-business Damselfly – 0, giant aggressive, predatory lake trout – 7, I thought as I quickly tied on the only Damsel I had, which had been wedged into the corner of one of my more obscure fly boxes. About ten hefty lake trout and one threadbare Damselfly imitation later, I had changed my whole attitude about them. If it’s Summer and I’m either float-tube or bank fishing a lake or pond, I carry a small box dedicated to Damselfly adults, along with a Damsel nymph imitation or three. You should too.

Oldies but Goodies: Since these next three attractor flies constituted about 80% of my childhood selection, I’ve decided to give them a place of honor in the Oldies but Goodies case. In order of rank when it comes to the success I’ve had with each of them over the years, the Rio Grande King, Renegade and Royal Coachman ought to comprise one nostalgic go-to corner of at least one of your fly boxes. After all, last I checked, trout still like to eat the same things today they did forty some odd years ago, right?

13. Rio Grande King

Hard to find these days, we used to fish this fly a lot on beaver ponds, but had success with them in mountain streams and high mountain lakes, just the same. We usually started out fishing them dry-dressed but, as impatient, competitive boys, soon abandoned drying and dressing them after strikes and hookups. It didn’t seem to matter anyway; the brook trout we were catching liked them dry, just as much as if they were soggy. Track the Rio Grande King down on the internet and buy a few in the 14 to 16 range. I suspect you’ll be back for more.

14. Renegade

As a young boy, I distinctly remember picking out flies with my dad. I’m sure he cringed at the cost every time my brother and I dumped a couple of handfuls of our faves on the counter, but he always kept us well stocked. On one such occasion, and surely, I expect, because of its cool name, I pleaded with my dad to buy me some Renegades.

A funny looking attractor, the classic Renegade pattern consists of a somewhat sparkly green body flanked at head and tail, respectively, by a spray of white and ginger-colored hackle. Trout seem to think it’s some sort of meadow fly, terrestrial bug or flying ant, but who cares? Let’s just say Renegades seem to draw fire exactly when other patterns wear out their welcome. Renegades run bigger, so saddle up with a few in sizes 10 to 16 and don’t be afraid to fish them moring, noon or evening. Yee-ha!

15. Royal Coachman

Among the prettiest of all common dry fly patterns, the Royal Coachman might be one of the most aptly named attractors in all of flydom. Picture a fancy, old western stagecoach with ornate red velvet cushions, green tasseled curtains and decorative gold and white appointments. Now shrink all of that into a dry fly pattern and you have the Royal Coachman.

Among my childhood array, this fly was either on hard core or as off as a fly could be. There was no in-between. I often threw one on in late Summer mornings, when all the meadow insects were active. That’s when the Royal Coachman seemed to rise to the top of the Colorado brook trout’s food pyramid. I’ve also been known to have Royal Coachman success right before dusk. Keep a few in the 14 to 16 range, and when not in use, have Jeeves keep them under glass.

16. Stimulator

Keeping with attractor royalty, another appropriately named fly, the Stimulator, is a staple Colorado dry fly. Stimulators feature a long, colorful chassis and head surrounded by a shock of elk hair hackle that makes the fly look a little like an arrowhead. I’m not sure if they named it because of what it does to a trout when it hits the water, or because of what it does to the angler when he or she sees it in their fly box. In other words, when things get slow, the Stimulator can often be the immediate antidote. And what angler doesn’t love tying on a big, nasty, colorful, easy-to-see fly that looks nothing like some sort of mutant butterfly, but that has been known to draw strikes like a supermodel draws frat boys.

I like the orange and green bodied Stimulators in sizes 8 to 14. Like many big attractors, Stimulators make good upper bugs for a trailed nymph dropper. My favorite combo is what I call Mr. Santa Clause: a green body Stimi with a red Copper John dropper. Merry flippin’ Christmas!

17. Irresistible

Don’t you just love the names of these flies? Another bulky, buoyant attractor, this less colorful cousin of the Humpy looks like an Adams fresh off a hot dog eating contest. If this fly were an actor-comedian, it’d be John Candy, John Belushi or Chris Farley (God rest their souls). And yet, I’ll never forget a day on the South Platte when my brother and I were getting skunked on one of the most beautiful stretches of winding ranch river I’d ever been blessed to fish. Other than the fly he’d managed to embed in the meaty part of his neck, just behind his right ear — the only thing either of us had caught all day — our fishing trip had been going along just fine.

Because it was so slow, both of us had developed a case of the LOIs (Lack of Interests) when, after a big sandwich and a Coke, I decided to tie on an Irresistible. What the heck, I thought, as I dressed it, dried it and laid a sweet cast just above and outside a swirl an intruding dead stump had made in the side of the river, when, bang, a sudden, monster take about made me soil my waders.

To that point, and by a long shot, the biggest trout I’d ever had on my line had attacked my Irresistible as if it hadn’t eaten in a month. My wife complains that I can’t remember the song she and I danced to on our wedding night, but that I can remember the fly I had on my line one day, long ago, when I was fifteen and fishing an obscure stretch of the Platte River with my brother. By the way, I’ll Always Love You by Taylor Dayne and a size 12 Irresistible on the end of a 9 foot tapered leader. Boom! Drop the mic.

18. Golden Stonefly

I love when I seine a river and find Stonefly nymphs in the mesh! It literally makes me giddy because some of my best days on various Colorado rivers have been characterized by prevalent Stonefly hatches. In my experience, Golden Stonefly patterns have worked well, but Epoxy Back Black Stones can be just as deadly. Stonefly hatches are known to cause trout to gorge like stoners (I know… ironic) on a just-delivered pizza. A good Colorado fly box features Goldens and Blacks, adults and nymphs, in sizes 8 to 14. If Stones are on, don’t be afraid to trail a Stonefly nymph off the end of a foam-based Stonefly adult. Believe me, there’s nothing like partying with the Stones!

19. Flying Black Ant

Now that I’ve veered into the terrestrial (land dwelling insect) zone, it’s important to say that, to the purist, terrestrials are not technically dry flies. They are terrestrials fished as dry flies or, in other words, floating atop the water. But who the heck cares if they catch fish, I say. And, among my favorite terrestrials is the Flying Black (and Cinnamon) Ant.

Most fly shops stock as many ant patterns as there are…well…ants! Nevertheless, my Colorado go-to is the traditionally tied Flying Black pattern. This basic ant imitation features a very ant-like segmented body bisected by a maroon colored hackle and white wing at mid section. In my life as a fly fisherman, the Flying Black Ant has been a rather reliable slump-busting bug. Many a slow afternoon has been salvaged by a splashy, into-the bank cast with a Flying Black or Cinnamon Ant imitation. FBAs can be especially productive when the afternoon wind kicks up. Stock a few in both colors, within the 14 to 18 range.

20. Amy’s Ant

Terrestrial? Attractor? Kitchen Sink? Whatever this fly is, it’s hodgepodge of thread, herl, flashabou, foam and wing materials make her look like a Carson City saloon madam from the days of yore. Better yet, trout will hit on her just as readily as would the lonesome range cowboys who frequented that ol’ west waterin’ hole. Metaphors aside, the Amy’s Ant pattern should be among the foundational components of a well-rounded fly box. Amy’s Ants come in a variety of body colors including red, olive and purple, and can be found in sizes 8 to 14. They, too, can be a great late afternoon slump-buster but also serve as a highly-visible strike indicator for a smaller nymph trailer or two.

21. Chernobyl Ant

It happens too often for me not to wonder: What synaptic misfire must occur in a fish’s brain that can make the most danger-discerning, leader-shy trout refuse a perfectly hatch-matched, well-drifted fly while, mere milliseconds later, fiercely annihilate a sloppily casted Winnebago like a Chernobyl Ant? This foamy “fly” looks more like a character on an episode of Spongebob Square Pants than anything found in nature. Nevertheless, it has the uncanny ability to render trout brain dead when its rather Zeppelin-like silhouette passes overhead. As with Amy’s Ants, Chernobyls come in a variety of styles and colors, and typically range in size from 8s to 14s. Big attractors and terrestrials tend to take up a lot of room in your fly box, so we suggest starting at least one separate box for such wide-bodies.

22. Parachute Hopper

My all-time favorite Colorado grasshopper imitation is the Parachute Hopper. Typically found in olive and tan, Parachute Hoppers feature a single arced lengthwise wing structure, a couple of segmented hopper legs dangling from its flanks and a white, easy-to-see parachute post. Parachute Hopper patterns are simple, elegant and deadly. Since many high-mountain meadows teem with smaller natural grasshoppers, I love that PHs come in sizes 8 to 18. It’s not unusual to catch ambitious fingerling trout on a Parachute Hopper only to wonder which one of the two was larger. And here’s a tip: cast these babies into the bank with a plop. Assume, like Evel Knievel, they underestimated the jumping distance across the river or got blown in by an unexpected gust. Add a little twitch to the drift and a shade-seeking trout may just sneak out for a meaty mid-afternoon snack.

23. Madam X

When standing over a fly case, I tend to lean traditional. Given the choice between the tried-and-true pattern and a fancier derivation, I will almost always opt for the classic. On one particular occasion, I had made my requisite stop at the local fly shop, nearest the river we were planning to fish. With glasses nose-low and tweezers in hand, I was loading up on a few fresh Parachute Hoppers when, suddenly, a very guidey-looking dude was standing at my side, ardently suggesting that I skip over the Parachute Hoppers and select a few Madam Xs instead. His vehemence rang true. I detected nary a hint of, “Aha! A fly-addicted sucker I can unload some of our iceberg inventory on.”

He said that if I liked Parachute Hoppers, I’d love the Madam X. Easily influenced but fighting my tendency, and ultimately fearful I wouldn’t have the right fly for the right conditions (FONH disease, remember?), I bought a few of both. And, man, was I glad I did! That day, late in the morning, I passed over the row of Parachute Hoppers in my box and tied on the sexier Madam X. No sooner had it hit the water when, BAM!, a big rainbow thrashed at it, darted upstream, skyed, and before I could say, “Holy shnikeys!,” snapped off my entire rig, half way up my leader. A few minutes later, once I’d found my heart, put it back into my chest, wiped away a few tears, and changed my undies, I re-rigged with stronger leader, tippet and a new Madam X, and the rest, as they say, is history.

Except for an elk hair wing structure and a set of four rubber legs, the typical Madam X looks a lot like a Parachute Hopper. They come with or without a parachute post but, for my aging eyes, I usually opt for the parachuted variety. You’ll find them in olive, yellow and other color and style variations. Stock a few from size 8 to 14 and, if you’re feeling particularly saucy, pack a few Madam X – Peacocks as well.

24. Cricket

A lot like my garage or basement on a late summer evening, no dry fly collection can truly be complete without a few Crickets. Another productive, slump-busting terrestrial, good cricket patterns look as much like a cricket as, well, a cricket. In other words, Cricket patterns are probably realistic enough to fool frogs and birds just as much as they do trout. And since they can’t make that incessant chirping noise, they are a lot easier to get along with than their annoying natural doppelgangers. Fished dry with a splashy landing and a twitch-enhanced drift, trout seem unable to resist them, especially on a warm and breezy evening. I say go big on your Cricket collection. Stock a few from size 6 to 12 and, for the sake of your marriage, be careful not to leave them out on the kitchen counter.

25. Foam Beetle (Hi-Viz)

Although Volkswagen is retiring the Beetle, you shouldn’t. In fact, the Black Foam Beetle (with a hi-viz orange spot on its back) must occupy a corner in your now-complete Colorado dry fly box. Rounding out your array, the Foam Beetle terrestrial, like its Cricket cousin, looks incredibly realistic and, a such, can induce electric trout attacks when nothing else seems to work.

These dark patterns have one drawback. Even with the hi-viz spot, they can be hard to see on the water. The answer? Try casting them near the bank, at the top of a slow-flowing run and then watch for a pronounced take near where you think your Beetle ought to be floating. Interestingly enough, Foam Beetles are much easier to see right after they’ve been consumed by a big brown, brook or rainbow trout! A few Black Foam Beetles in sizes 14 to 18 ought to balance out your box.

Final Thoughts

So, there you have it. My top 25 best dry flies for Colorado fly fishing. Since here at FFF, we’re not egomaniacs or easily offended if you (kindly) disagree, we invite you to share your favorite Colorado dry fly imitations in the comment field below.

And, if you’d be so kind, in the down-to-earth, willing-to-share spirit most fly fishing anglers possess, please let us know the what, why, where and how of your recommendations too.