system
Given the following post, respond as if you're commenting on Reddit:
human
What component/mechanism of a tree determines when and how it will branch off from the parent branch?

I was walking around my girlfriends cabin in the PNW, quarantining and all, and became fixated of the structure on simple moss/lichen & trees.

I recently dove into computer graphic generation and am now looking to figure out what mechanism forces a tree/moss to branch off from the parent branch and how? I want to recreate it with a graphic generating application - as I think it would be awesome to build a time lapse/simulation of the process. Plus, I have lots of time on my hand now.

Thanks!
gpt
The basic mechanism is controlled by two plant hormones. Auxin is produced in the apical bud of the main stem and existing branches and diffuses downwards from there. Sufficiently high auxin concentrations inhibit the formation of branches. Cytokinines, on the other hand, diffuse roughly from root to top and promote branch formation. Branching happens where those two overlapping gradients provide the right hormone ratio.