The American chestnut tree has dominated Eastern forests for centuries, but it almost disappeared when a foreign blight was introduced in 1904. Scientists have been trying to breed blight-resistant trees and recently planted several at the New York Botanical Garden, just steps from the blight's origins over one hundred years ago.
New leaves on this Indian bean tree emerge wine colored to chocolate, segueing to green in summer. White flowers are lavender-tinged. Though it can reach 40 to 50 feet tall and wide, it can be pruned hard to keep it shrubby. Zones 5-9. forestfarm.com
Among the valleys and foothills in Israel's Negev desert is a plant that can water itself, in a manner of speaking. The desert rhubarb (Rheum palaestinum) is the only known desert-dwelling species to have evolved a self-irrigating mechanism.