I was looking at this wall sticker and it gave me an idea!
We are a wood tribe. Traditionally everything we own was made of wood, so we used to cut down a lot of trees. But long ago the trees began to adapt. They grew thinner and thinner. Nowadays our trees are all 2D. It stopped us from cutting them down, it was chaos at first.
We use the trees differently now. Our houses are just trees growing in strategic places, and they are much more obliging now. Most will even grow their branches into doors and windows if you treat them well enough.