BRANCHING OUT
HIW, Stephen C
Dear
Trees have an amazing ability when growing branches to avoid branches that are already there. How do they do it?
A tree’s branches grow towards the light, and they usually avoid areas that will leave their leaves in the shade. Branches, which are usually covered in shadecreating leaves, are therefore avoided as the trees expand into open spaces. Trees are also able to sense nearby plants by picking up on far-red light that bounces from other branches. In some instances, forest canopies display light borders where branches and leaves of trees have actually stopped growing to prevent collisions with other plants. This phenomenon is called crown shyness. One theory for how this occurs is due to the wind making trees blow against each other. To prevent further damage to the branches’ flowers and leaves, their growth in these areas is slowed or stopped.