Twilight Forest

With their towering, cinnamon-colored trunks and dusky green canopies, ponderosa pine has long been a charismatic icon of the American West. Yet a quiet unraveling has begun: in the past decade, in a vast area from Santa Fe to the Sierras, more than two hundred million ponderosa have died. While some trees will survive in cooler places, scientists estimate that by mid-century less than five percen...