I think this is little bit complicated and we shouldn't judge only from one point of view. It is absolutely correct that the trees and all other plants (and animals) are connected with some kind of belief, are worshied and traditional part of the Japanese landscape.
Behind this, however, is the way Japanese are used to see the nature. It is not just the nature, it is a friend, a partner or an enemy, it is alive and it is a kind of society itself, only it follows rules and order different from ours.They are deities, they transform into humans and contact humans, marry them, kidnap them, protect them.
Japanese want to know and to be in contact with their nature, not just to watch it or use it...They have smaller amount of plants, because they want to know every type, for it is a living creature.
And as for the 4 seasons...The climat changes all over the world.