Branch lines

Today I’m in the grounds of a large rambling mental health hospital in south London; and before you ask, it’s because I’m working here.

Naturally I’ve got a camera with me and I’m drawn to a stunning cherry tree with bark like polished mahogany:

I think it’s a Tibetan Cherry Tree.

What I’d like to know is; what’s the evolutionary advantage of having red bark and what are all those splits about? With silver birch trees there’s the same pattern: a bright white bark with horizontal splits. In some trees the splits are a defence mechanism against elephants; they stop the elephants stripping the bark from bottom to top and killing the tree. I wonder what forces have been at play here?

I need to go and catch the Tube. That’s a different kind of branch line.