Of course you are right, Shanks, but the question remains... How did the fir tree keep its big root stiff enough to horizontally span twenty feet of empty space?

(Thats it! Like a schoolboy in full rut I had to say it. Done! Enough silliness. Now back to the important question in hand)

And Faldage, you sneaky devil, you too are right. It can be said that plants and trees can see even better than humans. Seeing is perception and the only way for humans to perceive light is through chemical absorption. The same as plants, but different. It is our brain/eyes that outlines and distinguishes separate environmental entities.
Plants don't need these nice refinements to survive this cruel hungry world. Good thing too, they can't run.