UK scientists have successfully germinated seeds from the critically endangered Japanese Birch, a species that has just 21 known trees remaining.
The seeds were collected last year during an expedition to a remote location in mountains near Tokyo.
Experts suggest that the remaining wild population of Betula chichibuensis is too small to sustain itself unaided.The young trees will be shared with other arboretums in an effort to help conserve the threatened species.
The International Union for the Conservation of Nature (IUCN) forecasts a bleak outlook for the tree species in the wild.In its Red List of Threatened Species, it observes: "The small population and restricted distribution... make it susceptible to natural disaster or disease.
"The species is also self-incompatible, requiring two individuals to be close enough to cross-pollinate one another, making seed production uncertain in small subpopulations."It adds that there was also evidence of deforestation and habitat degradation in the area where the remaining trees are found, "presenting a threat to the survival of this species".
During 2014, a team led by researchers from the University of Oxford Botanic Gardens, in conjunction with the University of Tokyo, embarked on an expedition to collect seed samples from the threatened birch trees.
Part of the team was Dan Luscombe, a dendrologist from the Forestry Commission's Bedgebury National Pinetum and Forest.He told BBC News: "I guess we got little lucky in terms of being there at the right time."It is found in a very, very remote location and it is not an easy place to get to. It has got very, very low viability so we were very lucky that we were able to collect a lot of seeds... as birch seeds shatter and shed everywhere, so once it has done that you will never find it."