The Myth: Every hiker, camper, and bushcrafter knows that moss grows on the north side of trees and rocks, and you can use it as a navigational guide if things go south … right? How about wrong? It's time we navigate through this moss myth and find a path to the truth.
The Reality: The term moss is a bit confusing to non-botanical people. Actual moss — of which there are over 12,000 species — is a small low-growing plant that's nonvascular and doesn't produce seeds. Moss is a spore-bearing plant, found throughout the world and commonly seen in damp shady places. To further confuse budding botanists, not every plant that's called a “moss” is actually a member of this group. Both algae and lichens are sometimes mistaken as a moss. But let's put identification aside to examine a simple truth they're all plants, and most plants grow better in the sun rather than the shade.
In my woods, and many other sites I've explored, the moss is heavier on the south side of the tree, which is the sunnier side. So if I bought into this myth, the moss would steer me in the opposite direction I intended. Of course, there are always exceptions. As plants grow toward the available light, they may grow better on any given side of a tree or rock. For that fact alone, this myth is busted.
But if we did have to create a takeaway from all this, it's safer to say that most moss species grow on the sunnier side of the tree, which would usually be the equatorial side of the tree.
Northern hemisphere moss generally grows on the south side, while southern hemisphere moss generally grows on the north side. And perhaps this is the source of the myth. Or it could be the green algae Pleurococcus, often found in a shady moist habitat (like the north side of trees in the northern hemisphere), though it can also be found on other sides of the tree in equal or greater amounts. So can you ever rely on moss location as a navigational tool? Hey, sometimes it's right — kind of like how a broken clock is right twice a day. So, no. The answer is no.
Alternative Uses: Busting this myth doesn't mean that moss is completely useless to a survivalist. Moss can be stuffed into your clothing or even your sleeping bag to add insulation and increase warmth if your clothing or bedding isn't doing the trick in cold weather.
Moss can also hold rainwater like a sponge. Just wring it out into a container, disinfecting it before drinking the water, just to be safe. Moss is astringent, allowing it to be a workable wound bandage (just keep it on the surface; never pack a wound with it). Dried moss is also absorptive, making it a great filling material for homemade baby diapers and menstrual pads. Just make your desired item from cloth, leaving an opening to fill the pad or pants with dried moss. Empty the item out when it's no longer absorptive. Then wash the cloth, refill it, and repeat. And after you've answered nature's call in the outdoors, a wad of soft damp moss makes an exceptional toilet paper substitute.
To finish with something less nasty, many dried moss species are great fire starting tinder. Seek out crumbly dry specimens, and hit them with the flame of a lighter or match for best results, though some species will light from sparks alone.