Still-living plants can themselves be shaped into bridges, tables, ladders, chairs, sculptures - even buildings. Known variously as botanical architecture, tree sculpture, tree-shaping, tree-grafting, pooktre, arborsculpture, and arbortecture, the craft is, essentially, construction with living plants.

Includes pictures from the root bridges of India to living islands!

1. Root Bridges of India

In the depths of northeastern India, in one of the wettest places on earth, bridges aren't built -- they're grown.

Grown from the roots of a rubber tree, the Khasis people of Cherapunjee use betel-tree trunks, sliced down the middle and hollowed out, to create "root-guidance systems." When they reach the other side of the river, they're allowed to take root in the soil. Given enough time a sturdy, living bridge is produced.

Because the bridges are alive and still growing, they actually gain strength over time, and some of the ancient root bridges used daily by the people of the villages around Cherrapunjee may be well over 500 years old.