The greenhouse effect

摘要

The oldest resident of Mobile, Ala., is Duffee Oak—tall, strong, and silent, and looking pretty good for a 300-year-old. The majestic tree is just one of the city's 3000 oaks that have passed the one-century mark. From the impressive Duffee Oak to the kaleidoscope of flowers adorning city streets, plant life is important to the 200,000 people who call Mobile home. Most of this fabulous flora has its roots in the city-run greenhouse.