Fencing in a tree might seem like a strange thing to do, even in the United Kingdom’s Kew Gardens—but this is no ordinary tree. It’s a Wollemi pine, a rare plant that grew among the dinosaurs. Long thought to have gone extinct, a small stand of the trees was discovered in 1994 by a national parks and wildlife officer in Australia’s Blue Mountains. Today, scientists know of fewer than 100 mature trees in the wild. Wollemi Pine International, a nonprofit, devised an unusual scheme to conserve the threatened trees and boost their numbers in the wild: Sell Wollemi saplings propagated from seeds and cuttings of the wild stand. They thrive outdoors, but consider keeping one in a sunlit room inside: The family of trees that the ancient pine belongs to is especially efficient at removing toxins from indoor air (ancientpine.com).      

—Alisa Opar