The Naturalist: Compass trees point the way home
Have you ever been on a hike and lost track of where you are? We have our phones to help us find our way, but we cannot always rely on these devices — service can be poor or battery levels can be low. Luckily, nature is there to help guide us, as long as we are tuned into her signs. One of these signs comes from the trees, who are reliable companions, helping us orient ourselves and find our way.
All plants need light. It is the catalyst for the process of photosynthesis, creating sugar for energy. Plant know this; they grow toward the light. Any plant lover with indoor plants sees this clearly with their plants leaning toward the windows. The primary light source in nature, and one necessary for photosynthesis, is our sun. The relationship we are looking for comes from the position that sun takes in our sky throughout the day.
The sun rises in the east and sets in the west. The most important time to plants is midday, when the sun is in the south (at least here in the northern hemisphere) and providing the most amount of energy. This relationship is flipped in the southern hemisphere, where the sun is in the north at midday. As trees grow, they angle their branches to capture as much light from the south as possible.
This manifests itself as more horizontal branches on the southern side of the tree and more diagonal and vertical branches on the northern side of the tree. You may also find that there are simply more branches on the southern side of the tree. This is very common with trees that grow alone in a field or meadow, or older trees in a new forest. But this angling towards south can be seen up in the canopy as long as south is the direction where the most light can reach the tree.
See if you can spot this pattern. Find a tree growing by itself or along the edge of the forest. Look at the angle of the branches, and try to find where south is. Then you can check yourself with a compass. You may be a few degrees off, but you still should have the general idea. Now you can call yourself a natural navigator!
Sam Nunes is an environmental educator at Woodcock Nature Center.