Dry flies are designed to imitate insects that may fall or land on the surface of the water and remain there without sinking. Typically featuring thickly stacked animal hairs, dry flies float along on the surface and imitate may flies, gnats and mosquitoes, to name a few. Often, an angler will dip the fly in a container designed to remove moisture or apply a small amount of fly float to help the lure stay on the surface.
Wet flies are designed to sink below the surface of the water. This fly imitates heavier insects that cannot be supported by the surface and may sink. Wet flies also imitate insects that have hatched under water and are making their way to the surface. Typically fished 1 to 2 feet below the surface, leeches and small crayfish may also be imitated.
Streamers are most commonly tied with feathers or a combination of animal hair and feathers. This fly is designed to imitate a small bait fish that is injured. In most cases, a streamer is somewhat larger than a dry or wet fly and is commonly used when fishing for larger trout species.
Nymphs are fished deep and along the bottom of streams and rivers because they are intended to imitate the larvae of insects. Although it is classified as a type of wet fly, the depth and manner that the fly is fished tends to put it in a category of its own. This is a productive fly because it gets the bait down to where the trout lives and feeds.
Terrestrial flies imitate all of those poor insects that just happen to fall in the water, struggle and drown. Bees, ants, worms, beetles and spiders are all imitated in fly patterns. Terrestrials may be fished dry or wet and come in a wide range of sizes.