Login with Patreon
Login with Patreon

Question of the Day: Tree Branching

Don’t ask me why, but I’ve been thinking about old-growth sequoias for the last few days.

A decade back, I had the chance to wander a mile into a sequoia grove, and it took my breath away. They’re beautiful, massive trees, and almost completely block out direct sunlight to the forest floor. Walking among them, it feels like you’re stepping into another world.

But it’s that complete lack of sunlight (at lower quarters) that’s raised a question in my mind…and despite some research, I can’t find the answer.

Here it is: For giant trees like these, I would imagine that the treetop photosynthesis is pretty critical. Packed (comparatively) close together, these giants must compete with one another for sunlight as they reach heights of over 300 feet. And since the average sequoia grove allows very light sunlight toward a tree’s base, any extra photosynthesis that the tree can squeeze in must be invaluable..

But let’s suppose that, halfway up a sequoia, a patch of sunlight consistently hits the tree’s trunk for 20 years. No sunlight hits the trunk above or below that spot for 50 feet…but right here…in this one spot…through some accident of placement…sunlight strikes.

Does a tree have a trigger response to that sunlight, such that it will branch out in response? Or is tree branching completely dictated by a set of fixed, geometric rules…and is unwavering? Keep in mind, I’m not talking about a branch bending or leafing toward the light once it’s already started growing: I’m talking about the tree creating a new branch in reaction to light’s presence.

The sign of a good education is the ability to research fields unknown to you. But in this case, my literature/art/propaganda background is failing me miserably.

Is there an aboriculturalist or arborist in the house? I’d love to share the answer with everyone, if you’d like to e-mail me or post in the Sheldon forum.