Could it be that this represents a system for generating music?

[oshfdk]

This plant has roots growing out of a human head. Doesn't this suggest that the plant itself is a manifestation of thoughts conceived within that head?

This highlights very well what I see as the main problem with your argument: it is an attempt to freely interpret images from a XV century manuscript without considering what these images would normally mean at the time. Faces/body parts/animals in roots were not rare and would be usually interpreted as cues about the name, shape or purpose of the plant. There are many threads about this on the forum, for example: You are not allowed to view links. Register or Login to view.