Why do trees have bark?
Bark is essentially the skin of a tree. It protects the inner layers of the tree, just like our skin protects our body from insects, disease and damage. It’s quite handy. Of course, the tree will survive if some of its bark is stripped away, just like we will survive if we scrape our elbow. However, if too much of this crucial layer is damaged, the tree will die.
Why are there different kinds of bark?
As trees grow, they get taller and wider, and when this happens, their ‘skin’ has to grow with them. Each type of bark responds differently to these growing pains.
Sometimes the outer layers of bark (the periderm) grow smoothly with the tree, stretching to for a single smooth layer of skin.
And other times, the periderm doesn’t grow quite as fast as the tree, which results in a rough, uneven layer of skin that breaks apart creating valleys and ridges.
Sometimes when the bark cannot grow as fast as the tree, it will form layers that seem to peel back and flake off.
As you can see, bark is a lot more complex a subject than it appears at first glance. It serves a very real and important purpose to all trees. Perhaps next time you get the itch carve your name into an old oak you will take a moment to remember what you’ve learned here and let the tree keep its lovely skin untouched.