Provisional tree seed zones and transfer guidelines for Alaska

Four hundred and eighty-six provisional tree seed zones were delineated within 24 physiographic and climatic regions of Alaska and western Yukon Territory. Estimated forest and potential forest land within altitudinal limits of tree species in Alaska was 51 853 000 hectares (128,130, 000 acres). Seed transfer guidelines and standard labeling of seed collections are recommended to reduce losses from maladaptation and maintain the genetic identity and productivity of future forests in Alaska.