I agree with others that it felt slow. Almost felt like a cookie clicker game where you would just wait and wait for things to happen. I could see it being expanded though. More trees, The ability to stretch your screen could add new things, although scrolling makes you managing harder, in an interesting way.
As for the game jam rule/idea, it was fine. In a way you do control yourself as a tree? I see what you mean though in that for most survival games you gotta run/move to survive. While the management was basic, it was good. The weird pacing and lack of other stuff to do made me give it a 3.
PS I liked the spaceship surprise. That got me good xD