U.S. National Vegetation Classification
The U.S. National Vegetation Classification (NVC or USNVC) is a scheme for classifying the natural and cultural vegetation communities of the United States. The purpose of this standardized vegetation classification system is to facilitate communication between land managers, scientists, and the public when managing, researching, and protecting plant communities.
Source: Wikipedia — U.S. National Vegetation Classification (CC BY-SA 4.0)