When the Royal Navy first “invaded” Ascension Island, it did so not with weapons of war, but with plants – creating what is said to be the only man-made tropical forest in the world.
The result is either a beacon for re-greening the planet, or a biological abomination, says writer Fred Pearce on the Yale Environment 360 website.
Isolation has meant Green Mountain has been “badly under-researched”, he writes – but it is now being hailed as a reason to look again at established thinking on the environment.
Because it works.
Bermuda cedar, Chinese ginger, Cape yew and Brazilian guava trees thrive on Green Mountain, alongside Japanese cherry trees and Madagascan periwinkles – and screw pines that grow higher on Ascension than they do on their native Pacific islands.
On St Helena, they’re following conventional practice by grubbing out alien species that threaten the survival of endemic plants.
If conservation officer Stedson Stroud took that approach on Ascension, there’d be almost nothing left. But actually, he says, some native ferns are growing on introduced species, and faring better because of it.
Three others, though, are believed extinct. A fourth was rediscovered by Stedson himself, and is now being propagated at Kew Gardens in London, ready to be reintroduced.
Green Mountain’s unnatural success is creating controversy among ecologists, says Fred Pearce.
He asks: “What are we to make of this confected cloud forest? Is it nature or a garden? Is it a beacon for re-greening the planet or a biological abomination?
“The British government’s environmental policy for the island is the ‘control and eradication of invasive species’ in order to ‘ensure the protection and restoration of key habitats’.
“But the policy has nothing to say about the protection of — or even ecological research into — the extraordinary novel ecosystem in their midst on which the indigenous species often depend.”
Click here to read the full article on the Yale Environment 360 website, published by Yale University.