American Society of Landscape Architects

At the most basic level -- in the way that the sky is blue and Jon Gosselin's fake-tanned skin is orange -- grass and trees and topiary and your other things-that-grow are green. It's tough to explain why all this is, so many years after seventh grade science, but chlorophyll and photosynthesis are involved and long story short plants are good for the earth and appealing looking besides. But while planting a tree is unquestionably a good thing -- PlaNYC, at least, thinks so -- there's more to a sustainable and healthy landscape than meets the eye. While it might all looks green to most of us, the new guidelines and planned rating system for green landscape development being offered by the Sustainable Sites Initiative makes it possible to get a more nuanced look at how green a specific project is.