I remember watching TV when I was a kid. The show was probably a rerun of Davey Crockett or some other nature-type program. One particular episode caught my attention. They were probably tracking Indians or trying to find their way out of the woods and the remark was made that moss always grows on the north side of a tree.

At first, I thought this to be a bit of folklore. Seriously, why would moss only grow on the north side of a tree. That makes no sense. Moss doesn’t have a compass. Moss doesn’t carry a map in it’s non-existent glove box. At the time, Mapquest and Google Earth did not exist. But still, moss doesn’t know how to turn on a computer or operate a GPS.
Alright, that’s silly but it is what I thought at the time.

It wasn’t until several years later that I finally realized moss does, indeed, tend to grow on the north side of trees. Moss does not only grow on the north side of trees, it also grows on the north side of rocks, garbage cans, and telephone poles.

You can see moss growing on the north side of this telephone poll.

Moss grows well in environments that are damp, cool, and shady. In a thick forest with full coverage of shade, moss will grow on all sides of a tree. However, if there is a break in the tree coverage where the sun penetrates, moss will find the sunny side of the tree inhospitable. Therefore it won’t grow where there is sunshine.

Think about the sun’s orientation in the northern hemisphere’s sky. During winter, the sun is well south of the equator. Since the sun is in the southern part of our sky, all shadows are cast north. During our summer, the sun reaches its azimuth on or about June 21. On this day, it is just barely directly overhead. Therefore, the north side of almost any object is still partially shaded. Moss, which loves the shade, is still protected from sunlight and continues to thrive.

I’ve always believed running a lawn care business gives us a higher sense of nature than most people understand. We learn how things grow by understanding their habitats and how they react with nature.