The way I see it is that its for maximum protection.
Tree trunks is that trees middle position.
tree trunks have xylem and phloem
Trunks
Lichen is a combination of fungus and algae. It grows on tree trunks.
Algae or mosses live on tree trunks.
Tree trunks are straight and branchless in their lower parts in their efforts to grow tall.
Woodpeckers tap on tree trunks. They are looking for insects to eat when they do this. Woodpeckers have a red head.
None.
The tree trunks are cylindrical because they grow from the center and outwards. They grow uniformly and this is evident from the rings when the trees are cut.
centimeters
The mangrove trees can have many trunks, but the banyan tree has both multiple trunks and above-ground "prop roots" that can grow vertically and horizontally.
Sometimes