Classification and description of world formation types

An ecological vegetation classification approach has been developed in which a combination of vegetation attributes (physiognomy, structure, and floristics) and their response to ecological and biogeographic factors are used as the basis for classifying vegetation types. This approach can help support international, national, and subnational classification efforts. The classification structure was largely developed by the Hierarchy Revisions Working Group (HRWG), which contained members from across the Americas. The HRWG was authorized by the U.S. Federal Geographic Data Committee (FGDC) to develop a revised global vegetation classification to replace the earlier versions of the structure