Green Roofs Grow in Boston "You don't have to mow or water this green roof. And probes will detect leaks. It's on top of the Aircuity Center for Green Building Technology. The entire building...an old mill...has been converted to showcase eco-innovations. On this day, though, a good old-fashioned crane hoists bags of dirt-like stuff...1,800 pounds each...up onto the roof." | 
