Fish numbers generally decrease as you progress downstream but, correspondingly, fish size generally increases. In the upper section near Aspen, 30- to 50-fish days are common, with most being less than 12 inches. In the lower section, floating through private water, most anglers will catch fewer fish in a day, but you can be sure to engage a few that will test your ability to land them without breaking off.

Rainbows and browns are evenly mixed throughout the river, but the higher elevation stretches with colder and faster water have a bias to rainbows while the lower stretches have a bias to browns. Near Glenwood Springs, a large population of whitefish, a plain but worthy opponent, can provide just as much action as trout. A tug on the business end of the line always makes for a guess as to which one -- trout or whitefish -- has inhaled the fly and is now showboating just out of sight beneath the current.

Having fished it often and at all times of the year, there is no bad time to fish the Fork. Pre-runoff is an excellent season -- few fishermen, hungry trout after a winter of want, and low, clear water make spring a great time of year to be on the river. About the only time to skip the Fork is during runoff. Sure you can catch fish in the mud if you work at it, but why bother? Head over to the nearby Frying Pan instead.

Summer gets busier with visitors, but there is plenty of river access to share. Oh, what a beautiful place to be! Summer in the Roaring Fork Valley sings a sweet song. Summer brings the opportunity to poke a dry fly into every pocket and riffle. If no feeding fish are evident, casting upstream with a nymph and weight into the longer, deeper pools usually brings a fish.

Anytime through October, cannot a mistake be made. Aspen and cottonwood trees lining the river bottom turn a brilliant yellow, the oak brush and serviceberry add a soft red contrast, while clear blue skies with moderately warm days make for a day in Colorado's mountain heaven. Summer crowds have dissipated and the trout have gained their summer weight, making for a challenging, low water, easy wading, sometimes sight-fishing experience to challenge a fish one-on-one.

Even winter can be very good in the lower stretches between Glenwood Springs and Basalt. Although winter river fishing can be challenging, most of the challenge is in getting over the common belief that fishing is just a fair-weather sport. But I say, any day I can go fishing is a "fair" day.

Winter flows are clear and at their lowest point, which concentrates the fish in the deeper runs, and your offering is easily put in front of fish and seen by them. Basically you can skip most of the shallow runs and holes. They just aren't there in the winter as they would be in the summer. Reading the water is more important than what lure or fly you use or what pound-test line you attach it with. So what if there is snow on the bank or ice along the edges? If the water is open and flowing in the middle, then there is opportunity to be had -- the fish continue to feed. Using neoprene waders and by dressing in layers, one can be comfortable fishing and wading all winter long.

Because of highly oxygenated, clean water, with a strong current, the Roaring Fork has a diverse and heavy population of insects. You will find most everything -- mayflies, caddis, stoneflies and midges. Terrestrials and streamers are also effective in certain situations. Streamers imitating sculpins as well as baitfish streamer patterns are deadly when float fishing the lower river. Attractor patterns work well in the less-pressured times of the year and sections of the river. During the height of summer pressure, local fly shops have unique and usually smaller patterns that you'll need to fool the fish that see a parade of flies.

Caddis flies are the most numerous. The early spring hatches become overwhelming, with days that you have to be careful breathing lest you inhale a few bugs. Blue-winged olives come early in spring, dissipate during the summer, and return in numbers again in the fall. Dry, nymph, emerger and wet fly techniques are all effective -- just pay attention to what is happening on or in the water and be flexible and changing with the progression of the hatch during the day. Pale morning duns create some delicate dry-fly fishing in the summer, but the biggest bang is the green drake hatch. Drakes are big bugs, strikes are explosive when the fish are on them, and there is no better time to consistently bring up the bigger fish to a dry.

Fishing a stonefly dry can be effective at times, but more fish are caught on a stonefly nymph pattern, either as a dropper under a big dry, or on a double nymph setup fished deep with weight. When nymph fishing, strike indicators may be necessary in the deepest of holes where you cannot see bottom. I prefer to use two very small indicators rather than one large one. With two, you can mend the floating line without moving the sunken fly. But in anything shallower, leave off the strike indicator and watch for the fish. You will see them flash. Develop a soft-slip strike technique that simply tightens the slack line and sets the hook.