Chicago, Green Roofs, & Greening

"The city first drew real attention to its greening efforts, when it planted a lush garden on the rooftop of City Hall. Now, be it McDonald's, Wal-Mart or the Apple store, businesses wanting a relaxation of density building rules or financing to help construct new offices are being convinced to plant so-called green roofs. The result: the city has planted or negotiated the construction of over 2 million square feet of rooftop gardens, more than all other U.S. cities combined." (Via Treehugger)