The northern island of Hokkaido, which is colder than Honshu, has something in common with Sakhalin: the cold regions are dominated by Sakhalin fir, Yeddo spruce, and Sakhalin spruce. These species are accompanied by Mono maple, Ermann’s Birch, Japanese red birch, and corktree. But that’s where the similarity ends: Japanese cedar and larch are completely absent here. Areas with a more moderate climate have more hardwood species, including Castor aralia, Manchurian walnut, Japanese snowbell, Japanese chestnut and Daimyo oak. In particular, the Manchurian walnut, a species that is almost indistinguishable from the American Butternut, feels completely at home here and has conquered much space in Group 40 through natural rejuvenation.