The USDA Natural Resource Conservation Service's Northeast National Technical Center in Chester, Pennsylvania produced Northeast Wetland Flora: Field Office Guide to Plant Species. The guide contains black and white illustrations, full species descriptions (with color photographs, illustrations, and small distribution maps), illustrated glossaries, an alphabetical species list (provides common and scientific names for 300 species of vascular plants), and a key to generalized plant groups. The guide may be browsed online or downloaded in .zip format.