In sharp contrast to Silver Creek, the Big Wood River, which flows directly though Sun Valley and the towns of Ketchum, Hailey, and Bellevue, offers easy fishing for wild rainbow trout. The medium-size mountain stream also offers dozens of public access points, a catch-and-release section, and great hatches.

The Big Wood's best hatch is the Green Drake, which usually comes off during afternoons in mid-June and extends into mid-July. Anglers armed with #12 Hair-winged Drakes and a stout pair of legs to challenge the heavy post-runoff currents can land lots of healthy 12- to 18-inch rainbows.

Hopper patterns work great on the Big Wood River during summer months.

The Green Drake comes off on different sections at different times. The hatch progresses upstream, but it might jump five miles in a day. Fortunately, if you find it one day, you can return to that spot the next day and the fish might still be locked onto Drakes--even if the insects aren't present.

Other mayflies to look for include Baetis throughout summer and fall (a #16 to #20 Parachute Adams, Gulper Special, or Sparkle Dun works well); PMDs in June and July (a #16 Light Cahill works); Yellow Sallies in late June and July (a #16 or #18 Stimulator works); Tricos in August, and the big Western Red Quill in October (a #12 or #14 Quill Gordon, Parachute Adams, Sparkle Dun, Gray Wulff, or H & L Variant works).

The Western Red Quill emergence is one of the finest opportunities to fish the Big Wood in relative solitude. In October, many of Idaho's outdoorsmen are chasing elk and deer, so you can spend warm afternoons and pleasant evenings on the water casting large dry flies to willing trout. Most of the river's rainbows (there are very few brown or brook trout) run from 12- to 18-inches long and a 22-incher is a monster.

Grasshoppers, ants, and beetles are extremely productive offerings during July, August, and September; and massive evening hatches of various caddis species come off from midsummer through fall. Standard #16-#18 caddis patterns, (Elk-hair Caddis, Sparkle Emerger, X-Caddis, and Stimulators) raise fish all season.

Unlike Silver Creek, the Big Wood remains open during winter for catch-and-release fishing. (Check with local fly shops for details on regulations, access points, and maps.) Midges are the standard offering during the cold months, although caddis larvae and mayfly nymphs draw strikes. On top, a #20 Parachute Adams or Griffith's Gnat can grab a trout's attention. Light leaders in the 6X and 7X range are required, because the Big Wood's trout congregate in slow-moving, flat-surfaced tailout sections when the water cools.

When choosing a section of river to fish, you should consider the following statistics. The Big Wood holds about 68 fish over 8 inches per 100 meters of water in the catch-and-release section, which runs from the Highway 75 bridge at mile-marker 122 upstream to the mouth of the North Fork.

From the Highway 75 bridge downstream to the Glendale Diversion Dam, where a two-trout limit applies (none between 12 and 16 inches), the Big Wood offers about 55 rainbows over 8 inches per 100 meters.

Downstream from the Glendale Diversion Dam, the water quality diminishes and trout numbers dip, although some large brown trout do move out of Magic Reservoir and into the river during late September, October, and November. Streamers like #4 Woolly Buggers and Muddler Minnows bring vicious strikes.