I definitely need to do another pass on the art so it's more obvious the root is a root.
But yeah the player is the interloper and the tree is trying to remove the interloper. The lore in my mind is that the player is an exterminator who has to kill monsters, but the tree doesn't understand the monsters are bad and just attacks outsiders. But it's all open to interpretation! Maybe the monsters aren't bad and the player is.