This section is from the book "Camping And Woodcraft", by Horace Kephart. Also available from Amazon: Camping and Woodcraft.
There are two questions that woodsmen will argue, I suppose, until doomsday. Having given my views on one of them, I may as well tackle the other, and then have done with controversy. Are there any natural signs of direction that will give a man his bearings when the sky is obscured ? Every one has heard, for example, that "moss grows thickest on the north side of a tree," and nearly every one has heard this as flatly contradicted. The general opinion seems to be that such signs are "important if true." The Indianr and white frontiersmen of fiction never have any difficulty in finding their way by noting where moss grows thickest on the trees; but when our novel-reader goes into the woods, compass in hand, and puts the thing to actual test, he probably will be disgusted to find that, in densely shaded primeval forest, there seems to be no regularity in the growth of moss, one tree having a thick layer of it on the north side, another on the east, another on the south, and so on. He is then ready to declare that the old saying is a "fake".
I shall endeavor to show that there is more in this matter than is generally credited. There are certain signs of direction that are fairly constant in given regions, so that by their help a native, or even a stranger who has good powers of observation, some patience, and a fair knowledge of the life habits of trees and plants, can steer his course without a compass, and without help from sun or stars. But let us clearly understand what is involved in this use of nature's compass-marks.
No universal rule can be established from such signs as the growth of moss on trees, the preponderance of branches on one side of a tree, or the direction toward which the tips of tall conifers point. Such things are modified by prevailing winds, shadows and shelter of nearby mountains, depth or sparseness of forest growth, and other local conditions. Everywhere exceptions will be found; if there were none, it would be child's play, not woodcraft, to follow such signs.
No one sign is infallible. A botanist can tell the north side of a steep hill from the south side by examining the plant growth: but no one plant of itself will tell him the story. So a woodsman works out his course by a system of averaging the signs around him. It is this averaging that demands genuine skill. It takes into account the prevailing winds of the region, the lay of the land, the habits of shade-loving and moisture-loving plants (and their opposites), the tendency of certain plants to point their leaves or their tips persistently in a certain direction, the growth of tree bark as influenced by sun and shade, the nesting habits of certain animals, the morning and evening flight of birds, and other natural phenomena, depending upon the general character of the country traversed. Moreover, in studying any one sign, a nice discrimination must be exercised. Let us glance at a few examples:
 
Continue to: