Be sure to follow the rule before you head out.
Rule: You must post before you leave.
In case there are seriously any "~~social Darwinists~~" eugenicists here:
https://www.amnh.org/exhibitions/darwin/evolution-today/social-darwinism
https://www.northwestern.edu/onebook/the-reluctant-mr-darwin/essays/darwin-morality.html
https://www.theguardian.com/science/occams-corner/2013/may/09/evolutionary-theory-gone-wrong-darwin
Fungi won’t trade if the tree is not giving enough nutrients. So while they don’t trade for profit they sure as hell aren’t engaging in charity.
Mutual aid, in other words.
A marketplace, of sorts
No. Flat out no. There is no competition and they're literally providing what they are capable of to take care of the others' need. Mutual aid is not a marketplace and the fact you instinctually thought of it that way tells me you need a book on capitalist realism.
There's no competition between trees? Hmm...
Not all competition is mediated via markets. Mushrooms will compete by injecting themselves into their adversaries using their own internal pressure.