Smog Threatens World’s Oldest Trees
The California forest that is home to the biggest and oldest living things on earth, the giant Sequoia redwoods, also suffers a dubious distinction. It has the worst air pollution of any national park in the U.S. Signs in visitor centers warn guests when it’s not safe to hike. The government employment Web site warns job applicants that the workplace is unhealthy. And park workers are briefed every year on the lung and heart damage the pollution can cause.
Although weakened trees are more susceptible to drought and pests, the long-term impact on the pines and on the giant redwoods that have been around for 3,000 years and more is unclear. “If this is happening in a national park that isn’t even close to an urban area, what do you think is happening in your backyard?” said Annie Esperanza, a park scientist who has studied air quality there for 30 years.