A set of three maps showing the length of the growing season, the start of the growing season and the end of the growing season for the fertile regions. A fourth map shows the average length in days of the frost-free period for the same regions.
List of 4th Edition Maps
List of Map Archive Collections
Download full size map ( 1,729 KB JPEG, 3030 x 2130 pixels )
Download Map in PDF ( 1,795 KB, Adobe Acrobat Reader required )