Betula chichibuensis

Betula chichibuensis, commonly known as Chichibu birch (Chichibu-Minebari in Japanese), is a species of birch native exclusively to limestone outcrops in the Okuchichibu and Kitakami Mountains of central and northeast Honshu, Japan. The tree is rated as Critically Endangered on the IUCN Red List due to its extreme rarity and limited range. In 1993, only 21 B. chichibuensis trees existed in the wild. Although several other small populations of the tree were discovered in the 2010s, including the Kitakami populations, the Chichibu birch remains very rare. Ex situ conservation efforts to prevent the species' extinction are ongoing, including at the University of Liverpool's Ness Botanic Gardens and the Bedgebury National Pinetum....read more on Wikipedia.