The USDA Forest Service has recently published a fully revised and enlarged edition of Robert G. Bailey’s ecoregions map of the United States.
The 24” x 36”, 1:7,500,000 color map depicts 52 regional ecosystems, from tropical rainforest to arctic tundra to subtropical semi-desert to temperate steppe to mountains with altitudinal zonation.
Part of USDA Forest Service Miscellaneous Publication Number 1391, Description of the Ecoregions of the United States is available at no cost from the author at: USDA Forest Service, Ecosystem Management, 3825 East Mulberry Street, Fort Collins, CO 80524