SUPPLEMENTAL VOL. 1 USDA Unveils New Plant Hardiness Zone Map The U.S. Department of Agriculture (USDA) today released the new version of its Plant Hardiness Zone Map, updating a useful tool for gardeners and researchers for the first time since 1990 with greater accuracy and detail. The new map — jointly developed by USDA's Agricultural Research Service and Oregon State University's PRISM Climate Group — is available online at http://www.planthardiness.ars.usda.gov . ARS is the chief intramural scientific research agency of USDA. For the first time, the new map offers a Geographic Information System based interactive format and is specifically...