Botanist's Lens: Endemic, Rare Living Collections
The Dell with a Dawn Redwood tree (Metasequoia gylptostroboides) and the South River
London Town's garden is a sanctuary of its own. The beautiful South River wrapping around its edges makes every section of the garden feel serene, but what gives the gardens its true depth of serenity is the fact that it is home to several living collections that teach us about endemism, conservation and evolution.
What does endemism mean? "Endemism refers to a species that is restricted to a particular geographic region as a result of factors such as isolation or in response to abiotic conditions." (Source)
"Endemic plant species are usually more vulnerable to anthropogenic threats and natural changes and, therefore, hold a higher extinction risk. Ex situ conservation measures must be undertaken to support the conservation of these species". https://pubmed.ncbi.nlm.nih.gov/32182892/
Dawn Redwood tree (Metasequoia gylptostroboides) by the Visitor Center
One easy example of endemic species is: Sequoia sempervirens, coast redwood or California redwood. This species is different than Metasequoia gylptostroboides which is commonly called as Dawn Redwood.
London Town is home to four outstanding Dawn Redwood specimens. Dawn Redwoods are endemic to China. Coast redwoods on the other hand are endemic to the costal area of Northern California and Southwestern Oregon. Now Giant sequoia (Sequoiadendron giganteum) is a whole another 'big' story. They are the oldest and largest living trees on earth and they are endemic to Sierra Nevada range in central California.
Endemic plants are unique, rare and to be treasured. They have higher risk of being threatened with extinction because of many factors, isolated geographic locations for one. Botanical gardens are an excellent repository for ex-situ conservation, education and display of these rare endemics. However, only some endemic species can be introduced and survive outside their non-native habitats.
"Metasequoia glyptostroboides (dawn redwood) (Taxodiaceae), a living fossil endemic to China, may be the most successfully recovered threatened species, with many more individuals and a much wider distribution than fossil records indicate." https://www.jstor.org/stable/3591025?seq=1
Hakone macra grass and Strachrus praecox
Two other unique rare gems found at London Town are: Hakone macra and Stachrus praecox. Hakone grass is now common in nursery trade, it is endemic to the hakone region of Japan near Mt. Fuji. Stachyrus praecox is also one such unique plants. "Stachyurus praecox is a deciduous, endemic pioneer shrub, common along forest edges in warm temperate Japan". https://herbaria.plants.ox.ac.uk/.../ST/Stachyuruspraecox
Hope you enjoyed a small glimpse of the rare living collections of a unique garden sanctuary, London Town. There are many more living collections that are awe inspiring.