Fly fishing can be roughly divided into four categories: wet fly, dry fly, streamer and nymph fishing. The latter, a variation on wet fly fishing, appeared in this country at a much later time than the other three.

Regarded by many as the most difficult form of angling, nymph fishing can become your most reliable technique. It offers more opportunities to take good fish than the older methods, but it does require a little more emphasis on experience and concentration.

You will have many more takes on a nymph fly but most, at least to the angler accustomed to the rise of a fish to a dry or the solid tug of one taking a streamer, won't be so readily apparent.

For this, experience is the best teacher. I recall a pupil in one of my fly tying courses some years back calling and saying: "Bob, could I go fishing with you one of these first evenings and just watch? I have been trying to catch a trout on a nymph all season with no luck".

Part of each tying course was devoted to nymph making and this included a short discussion about fishing them with special emphasis on watching the line closely for any indication that a fish was mouthing the fly. I remembered Tim had been interested in nymph fishing and particularly so in the part about using the line as a strike indicator.

A couple of evenings later I met Tim at Mt. Vernon Creek. True to his word, he left his rod in the car and followed closely along the creek. When I would approach a pool on my knees, he would do the same and watch over my shoulder as I cast and fished out the drift. On the second or third cast the line paused almost imperceptibly. I lifted the rod tip and a good fish was on.

Tim said, "My line has been doing that all season!"

Remember, practice to get your fly out without false casting. Leave throwing it back and forth in the air to the dry fly fisher who wants the fly to float.

Here is how to tie a good all-around nymph variously known as the peacock nymph, lead wing coachman nymph and sometimes just plain may fly nymph, it will be a useful addition to your fly box.

Peacock herl, its principle component, has an iridescent insect-like look in the water and when wound on a hook simulates the gills that living nymphs breathe with.

By varying proportions this sequence of construction can be used to suggest most may fly, dragon fly, damsel fly and stone fly nymphs. Materials, of course, will vary.

I have had good luck fishing for trout with this pattern in size 12 and 14 on southern Wisconsin streams and taken many nice bass from northern lakes with it in size 8. In large sizes the peacock herl version is a dandy dragon fly nymph imitation.

If you can tie wet and dry flies, nymphs will give you no trouble.

First clamp a 2X long hook in the vise. Size 12 is a good all-around trout and pan fish size.

Secure it by the bend so that a little of the point is exposed, the shank is parallel to the table top and the eye end extends to your right (if you are right handed).

Make a base for the material by first coating the hook shank with fly head cement then, starting at the eye end, wrap tying thread over its own end and spiral it back to the start of the bend and half-hitch it there. Coat this wrapping with cement also.

Select five or six stiff brown hackle fibers for a tail and tie them on top of the existing half-hitch with a thread wrap and a half-hitch and cement on each knot. Keep a piece of sandpaper or a little steel wool handy to clean the needle.

The tail should extend out about one-half to three-quarters the length of the hook shank and flare a little horizontally.

Tie one end of a two or three inch length of fine flat, gold tinsel on in the same place and the same manner for ribbing.

Select three or four strands of peacock herl for the body and secure by the tips in the same fashion. Put a drop of cement on these knots.

Now advance the tying thread by winding it forward and secure with a half hitch about two-thirds of the way along the shank. Cut a section about a quarter of an inch wide from a dark gray duck wing feather.

Tie this by the tip on top of the hook shank and directly over the previous half-hitch so that the butt of the section projects rear ward and upward. Do this with another thread wrap and half-hitch. Always put a drop of cement on each half-hitch.

The section just tied on will be folded forward later to form a wing case covert.

Now, grip the strands of peacock herl and, treating them as a single strand, winding over and away from you, wrap them side-by-side up to where the wing covert feather is tied on and tie off with a thread wrap and a half-hitch. Cement this knot.

Rib the body by spiraling the tinsel ahead and tying off in the same manner. Cement this knot also. Advance the thread ahead of the wing feather and half-hitch tight up against the wing but in front of it. Cut off and discard the excess tinsel and herl.

Select another bunch of herl (a little thicker than the first) and tie these in by the tips. Advance your tying thread by spiraling it ahead and secure with a half-hitch about 3/16 of an inch back from the hook eye. Always leave a little more room for the fly head than you think you wilI need.

Now, wind the herl ahead, in the same manner as before, to make the thorax (this should be about twice as thick as the abdomen you just wound) and tie off where the thread is half-hitched. Cement this knot.

Select a soft brown hackle feather, stroke it to make the fibers standout, trim the fuzzy fibers from its butt and tie it on where the thread was last half hitched. Do this with the concave side towards the hook, and the tip extending rear ward, by making a couple of wraps with a half-hitch around the trimmed feather butt and the hook and cementing this knot.

Grip the hackle feather by the tip and make two or three turns around the hook tight against the thorax you just made just back of the last half-hitch. Catch the feather tip with a turn of thread and tie off with a half-hitch right on top of the one that secured the feather's butt.

Cutoff and discard the excess feather butt and tip. Also the excess herl from the previously formed thorax if you haven't already done so.

Now, cut the hackle fibers off on top of the fly and fold the wing section, that has been left standing all this time, forward to form a cover for the thorax and hackle and tie off. Cement this knot. Whip a head, cement it well, cut off the thread and the fly is done.

The ribbed part of the fly is its abdomen and the enlarged part in front is the thorax. The cover over the thorax suggests the wing case. Tinsel is used for ribbing because it simulates the translucent joints between the abdominal segments on the natural. The thorax is opaque so that is not ribbed.

The hackle imitates the insect's legs. The rule that says wet fly hackle should touch the hook point when stroked back doesn't apply here because extra long hooks are usually used. The dry fly rule that hackle fibers should be about one and one-half times as long as the hook gap is wide is more applicable.

Nymphs usually have stubby feet so trimmed hackle looks natural for their imitations. Trim it before you wind it, though.

Shrimp or scud and sow bug imitations are usually just plain hackle wet flies. They are often made with muskrat or mink fur bodies. They may or may not be ribbed with tinsel. To my way of thinking, tinsel ribbing helps give the illusion of translucency which many scud and freshwater shrimp are.

Sometimes scud and shrimp patterns have a "shellback". this is made in the same way as the covert for the peacock herl nymph above except that it is tied on at the rear and brought forward over the whole fly.

Weighting is done by wrapping lead wire around the hook before the fly is constructed. A weighted fly will usually swim upside down so plain hackle flies are best here because there is no top or bottom to them.

For most of our small streams, weighted flies are an abomination because they will wrap themselves around grass, brush or anything else they might touch in casting, like those bolos that South American cowboys use.