Fly fishers utilize four types of flies, with each designed to imitate a particular phase of an insect’s life or a particular kind of aquatic life. Basic types of flies are dry, wet, nymph and streamer.

Dry-fly fishing is the most-exciting type of fishing because it is more visual than other methods. You can see a trout rising to an insect, and you can see a trout rising to an artificial dry fly. Hook a rising trout on a dry fly, and if that doesn’t get your adrenalin pumping, take up bowling.

A dry fly is constructed so that it settles delicately and naturally on the surface of a stream and floats into the view of an unsuspecting trout. Basic components of a dry fly are hackle, wing, body and tail. Hackle, made from the long, slender feathers of a rooster, gives the fly its floating qualities. Hackle is wound in a full circle around the hook, just behind the eye. The stiffness of the hackle feathers allows the fly to sit on the surface. In addition to helping the fly float, hackle also simulates the wings, legs and tail of an insect. Dubbing, usually made of animal fur and secured with thread, forms the body of the fly. Various other materials such as tinsel, floss and peacock herl are designed to give the fly a realistic appearance.

Common dry-fly patterns are: Adams (male and female), Blue-Winged Olive, Royal Wulff, Royal Coachman, Caddis, May Fly, Thunder Head, Quill Gordon, Hendrickson, Cahill, Midge, Gnat, and Stone.

A wet fly looks very much like a dry fly except that it doesn’t float on the surface. It imitates a drowned surface insect, an emerging nymph or an adult female that goes beneath the surface to lay its eggs. The basic components of a wet fly are about the same as a dry fly, only the fly is usually tied with soft hen hackle instead of stiff rooster hackle to make it more absorbent. A wet fly generally imitates the emerging stage of an insect, and the fly is fished beneath the surface and given occasional tugs to simulate a swimming insect. Most wet flies are tied with the feathers and hairs lying down along the shank of the hook so that the fly will slide easily through the water. Wet flies often are used as droppers off dry flies.

Common wet fly patterns are: Black Spider, Coachman, Blue Dun, March Brown, Gold-Ribbed Hare’s Ear, Dark Cahill, Light Cahill and Zulu. Dry flies can be tied wet by using softer hackle.

Neither wet flies nor dry flies have to be exact imitations of an insect, merely a reasonable approximation. Looking up to the surface, a trout gets a distorted view of a floating dry fly. A wet fly usually is fished in fast water, and a hungry trout doesn’t have time to scrutinize it. 

Nymphs, however, have to be close duplications of the real thing since they represent the larval stage of an insect when the insect has very little swimming power. Nymphs tumble along the bottom or lie on the bottom. Since there is little distortion beneath the surface, a trout has adequate time to examine the fly. If the fly doesn’t look like the real thing, the trout will go elsewhere to eat. In still water, nymphs make up about 90 percent of a trout’s diet, and nymphs are available food year-round.

Nymphs are cast upstream above feeding trout and allowed to tumble naturally downstream to them. In dry-fly fishing, the fly always is visible, but in nymph fishing, you see neither the fly nor the trout taking the fly. Nymph fishing requires time and patience to master because you have to learn to detect a strike, which sometimes can be as subtle as a slight pause in the drift of the leader.

Common nymph patterns are Stick Bait, Hare’s Ear, Tellico, Girdle Bug, Pink Lady, Secret Weapon, Pheasant Tail, Prince, and Zug Bug.

Streamers, also called bucktails, are the flies fishers use when they want to catch big browns and rainbows. Streamers imitate swimming aquatic life such as minnows, dace, and sculpin. They are usually stripped through the water to simulate the darting, swimming patterns of small fish. Streamers come in large patterns, anywhere from a No. 10 to a No. 4.

Common streamers are: Muddler Minnow, Woolly Bugger, Black Nose Dace, Shiner and Threadfin Shad.

Other flies, called terrestrials, imitate various crawling, flying or hopping insects such as Japanese beetles, grasshoppers, ants, inchworms and crickets. These flies can be fished either beneath the surface or on the surface. Best time to use terrestrials is early summer to first frost.

Size is an important, although not critical, factor in fly fishing. A fly should be as close as possible to the size of the insect or aquatic life it is  imitating.

A trout fisher’s fly box should include all versions of the fly to ensure a successful outing on a mountain streamers.