In looking up the urban legend that moss only grows on one side of the tree and this can help you when you are lost in the woods – I found it is in fact (mostly) true! In the northern hemisphere, the south side of things receive the sunlight, and since moss likes to grow in cooler places with less sunlight, it tends to grow on the north side of trees. Now in dense forests where hardly any light shines through, it can be found surrounding the tree, but it is usually still more dense on the northern facing side. I also learned that ski slopes are usually on the north side of the mountains, since they are cooler as well.
And there’s your science lesson for the day!