Can you name three species that intentionally modify their environment to suit themselves? You probably thought of beavers. It’s very obvious that they take down trees, dam creeks, and create ponds in order to make habitat that suits their needs. Humans might be on your list. They dramatically alter their environments by rerouting waterways, tearing down hills, filling in ravines and much, much more.
All these changes are intended to make it more comfortable and convenient for humans to live there. Most people don’t think of the third species, though. Trees also modify their environment to create better habitat for themselves. The difference is that humans and beavers change things relatively quickly. Trees take a comparatively long time to adapt their environment to their needs, but they do make intentional changes.
Trees create communities and many of the things trees do in their communities are analogous to the things humans and beavers do in theirs. Trees “parent” their offspring, shading young trees and restricting the amount of light that gets through to them. Doing this forces the young trees to grow at a slower speed, making them sturdier and healthier. Trees also feed their offspring by sharing nutrients through their root system. In addition to their relationship with their offspring, trees also maintain a relationship with important “ancestors.” An ancient tree that was cut down or falls on its own can’t photosynthesize since it no longer has leaves. Other trees in the community will continue to feed this important community resource. It is a resource because the hundreds of years of experience form something akin to a library—it’s a resource of knowledge that the community can draw from. So, it’s in the best interest of the community to maintain that resource.
Trees also manage the climate of their environment. A community of trees coordinates the release of water vapor to cool the air and spreads their leaves and branches to block the sun and trap the cooler air. They “invite” beneficial plants to join their community. These beneficial plants increase the availability of important nutrients.
Additionally, trees create more soil as their leaves and branches fall and decompose. The roots of trees sculpt the landscape reshaping hillsides and creek banks—increasing soil stability. Trees break down rocks as their roots exploit weaknesses and cracks. They create an environment that establishes beneficial habitat for themselves and, by extension, other forest residents. When you visit the Preserve, see if you can spot ways trees are creating the environment that helps them, their offspring, and neighboring plants thrive.
– Katha Miller-Winder, President