Many know that moss grows on the northern side of a tree, which helps with navigation in the woods. However, is this sign universal? Ecologists warn of the need for caution when using plants as navigators.
For centuries, travelers and explorers have used natural landmarks for navigation: stars in the sky, wind direction, and of course, moss. The common belief is that moss grows exclusively on the northern side of trees, making it easy to determine directions if you get lost in the woods. Caitlin Fong, an ecologist from the University of California, does not dispute this viewpoint. She explains that moss prefers moist and shady conditions; otherwise, it dries out quickly. As one moves north from the equator, sunlight reaches the ground at an angle from the southern side rather than vertically. As a result, the northern side of objects receives less light and remains shaded.
However, this rule applies only to the Northern Hemisphere. In the Southern Hemisphere, the situation is reversed: sunlight predominantly illuminates the northern side. For example, in Australia, moss mainly grows on the southern side of trees. Architects need to consider this when designing buildings to ensure that windows face the sunny side, Fong notes.
Nevertheless, one should not rely entirely on plants. Moss lacks roots and a vascular system to transport water and minerals, making it vulnerable to moisture loss — which is why it prefers shady spots. However, in nature, many factors can create shade and increased humidity, allowing moss to grow in different directions even in dense forests. Therefore, one should not completely abandon the compass. If you do get lost, it is wise to examine as many trees as possible and determine where moss is most frequently found and whether it is shaded by other forest objects.
