The saying goes “moss always grows on the North side of trees”. While it’s more complicated than that, there is some truth. Moss needs cool, damp conditions in order to grow because they absorb water through their leaf-like structures. Sunny spots dry out whatever moisture they have since there is no soil to hold onto water. Their root-like structures called rhizoids keep them anchored to their preferred growing substrate. If there are no obstacles, the North side does not receive direct sunlight. However, areas could be shaded by other obstacles like rocks, other trees, canopy leaves. So don’t rely on moss pointing you in the right direction if you are lost in the backwoods with lots of canopy cover.
Lichen and fungi and moss, oh my!