Coming now to the question of when and where to fish the floating fly on water evidently suitable therefor, in view of the fact that the American dry fly caster of necessity usually fishes the water rather than the rise, it is evident that the fly-fisherman must depend upon his knowledge of trout haunts and habits in the determination of this matter. Given a stream fairly abundantly stocked with trout, either fontinalis, the native speckled brook trout, fario, the brown trout, or with rainbows, where the most, the best, or any trout will be found, is to a considerable extent a matter of time and temperature—notwithstanding which the careful angler, and in particular the dry fly fisherman, will proceed to fish all the water except such as may be known to be barren of trout.
In general, trout will be found at the head and foot of riffles and rapids; at the head and tail of pools; in the lee of rocks in swift runs; under shady, shelving banks and boulders and similar "hides"; particularly in warm weather, where small, cold, spring-fed brooks enter the trout stream; and anywhere where the set of the current, as in little bays and on the bends, is such as to collect insect food in quantity. Really the angler need only remember that trout require cold, moving, and aërated water, especially brook trout, and the same thing is true of brown trout in somewhat lesser degree.
To enlarge upon the matter further would be impracticable here. In point of fact, stream experience alone will enable the angler to spot confidently and with precision the places where a good trout may be lying. Each trout taken by an observant fly-fisherman adds to the angler's sum of knowledge regarding "where the trout hide"; it would seem that a mental picture of the place is retained subconsciously—the trend of the current, the character of the banks and stream-bed, and where, in relation to some prominent object, such as a large boulder or possibly a sunken log, the trout rose; all these and other details are noted and mentally recorded, and eventually the angler, by the correlation and association of these mental pictures, comes to recognize instantly, almost to a matter of inches, the places where a rise may be expected. That an experienced fly-fisherman can tell "almost to a matter of inches" where a trout will rise may seem, to the casual reader, to be putting it rather strongly. However, inquiry of some sportsman of many seasons' experience with the fly-rod will definitely settle the matter one way or another.
While, indeed, the character of American trout streams is such as to definitely discourage fishing the rise purely, it cannot be too strongly emphasized that the dry fly-angler, while fishing the water, should constantly be on the lookout for a rising trout. Time and time again, while fishing a good pool or run where the rise of a trout could be noted, the writer has spotted rising fish to his very practical advantage. In this regard it might be well to note the fact that a rising and feeding trout creates very little disturbance on the surface of the stream, and does not, in accordance with the popular idea, leap above the surface; sometimes there is a slight "plop," and at times a little spray thrown, but the fish very seldom shows itself, and twenty trout could rise within the vision of an inexperienced and inattentive angler without attracting his attention. Upon glassy, still pools the subsequent widening circle of ripples tells the plain story of a rise; in a current, however, the actual rise must be seen—and often is if you are looking for it.
CHAPTER VI
How to Fish the Floating Fly
Presuming that the angler has outfitted correctly and that he is a fly-caster of average ability, and further assuming that the stream he is on is at least fair dry fly water—which he will fish upstream manipulating the fly with whatever skill he may command with the purpose of imitating the action and appearance of the natural fly floating down on the surface—success, then, is predicated wholly (apart from the question of the right fly at the right time) upon the manner in which the fly is fished. Under this head—how to fish the floating fly—there are many points for consideration, of which not the least in importance is the matter of drag.
Drag occurs when the artificial fly travels at a rate different from that of the natural fly in the same position—either faster or slower or with a tendency to move across or contrary to the current. It is caused by conflicting currents which exert dissimilar forces upon fly and line. The natural dun coming down without restraint, of course, from line or leader, is affected only by the current whereon it floats; the artificial fly, attached to line and leader, several feet of which must often lie upon the surface, is subject not only to the rate and direction of the current upon which it floats, but also—unless the angler so handles his tackle as to prevent it—to the force and direction of the currents which play upon the line and leader.