The tree idea goes back to the silly idea of “schroedinger’s cat,” which tries to claim a cat is either alive or dead in a box depending upon if you look. It fails the test of logic. Whether an observer is present makes no difference (unless of course the cat is in a sealed box and is desperately hoping an observer will open the box so it can get air). It’s surprising how many scientists forget that quantum physics is a mathematical representation of how the universe works at a tiny level, based on probability. Trouble is, that probability itself is NOT actually what is going on at a given moment, it’s a representation of what is going on, and it allows equations to be solved and general patterns to be predicted. A given atom is not going to have the charge/spin at any given moment that schroedinger’s equation would indicate, but when you have a massive group of them, at least some or all of the overall group will perform like the equation represents.