Environmental Engineering Reference
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patches of natural soil on the mountain. The farm grew introduced fruit trees like guava from Brazil,
Cape gooseberries from South Africa, bananas from the Far East, and lychees from China. Then there
were vegetables such as cabbages, spinach, and potatoes, as well as some grains, herds of South African
pigs, and cattle and sheep from England.
The farm operated until the 1990s and is now overgrown. But it is the trees that fascinate in the
twenty-first century. On this volcanic hulk Britain planted specimens from across its global empire. In
the early days, the sailors grew New Zealand flax to make rope for ships and straight-trunked Norfolk
pine for masts. British colonial botanist Sir Joseph Hooker—a friend of Darwin and future head of the
famous botanical gardens at Kew in London—visited in 1843. He came up with the idea of growing
trees to gird the mountain and green the arid island. The archive preserves a letter that Hooker wrote
in 1847, with a long list of recommended introductions to ensure that “the fall of rain will be direc-
tly increased.” The new vegetation on the mountaintop would scavenge moisture from passing clouds,
he promised. Down the slopes, trees and bushes would encourage soil growth. Hooker's ambition was
nothing less than remaking the volcanic island—or “terra-forming” it, as Stroud and Catling put it.
In 1845, a naval transport ship from Argentina delivered the first batch of seedlings. In 1858, more
than two hundred species of plants arrived from the Cape Botanic Gardens in South Africa. In 1874,
Kew sent seven hundred packets of seeds, including those of two types of plants that especially liked
the place: bamboo and prickly pear. The sailors got to work, planting several thousand trees a year. The
bare mountain was soon verdant—and renamed Green Mountain. An Admiralty report in 1865 praised
the new cloud forest. The island “now possessed thickets of upwards of 40 kinds of trees besides nu-
merous shrubs,” it said. “Through the spreading of vegetation, the water supply is now excellent, and
the garrison and ships visiting the island are supplied with an abundance of vegetables.”
3
Today the island has around three hundred introduced species of plants, says David Wilkinson, an
eclectic botanist from Liverpool John Moores University in the United Kingdom, who made a rare re-
search visit to Green Mountain. Many are spreading. Above about two thousand feet, Green Mountain
is now completely vegetated. On my walk back down the mountain, Stroud pointed out coffee bushes,
vines, monkey puzzle trees, jacaranda, juniper, bananas, buddleia, palm trees, clerodendrum, the pretty
pink flowers of the Madagascan periwinkles, and the bell-shaped blooms of the American yellow trum-
petbush. He confirmed that the vegetation captures more cloud moisture on the mountain, just as Hooker
had hoped. This even though there has been a decline in rainfall in the surrounding lowlands.
4
The Victorian terra-formers did not just bring plants. The island's military inhabitants joined the
nineteenth-century craze among expatriate Europeans to fill their new worlds with birds and animals
from home. The regular ships to Ascension brought hedgehogs and rooks, ferrets and owls, bees to pol-
linate, and guinea fowl as quarry for hunting. Ascension never quite became the “Little England” that
the human colonists had hoped. Of the introduced birds, only the tropical canaries and mynahs have
stuck around. But the mammals did better. Rats and rabbits can still be found in numbers, along with
feral sheep, cows, and chickens let loose from the now-abandoned farm. And donkeys—descended from
the beast of burden that once carried water from mountain springs to the coastal garrison—still wander
the landscape, eating mesquite fruit and getting hit by cars.
The introduced rats were trouble. They swiftly saw off a couple of endemic birds, the Ascension
crake and the Ascension rail, and possibly also a night heron.
5
For a long time, there were also feral cats.
Originally brought in to control the rats, they tyrannized the seabird colonies, forcing most to nest in-
stead on a tiny offshore mound known as Boatswain Bird Island. Ornithologists began a cat-eradication
program, and the last cat was hunted down in remote Cricket Valley in 2006. Since then, boobies have
begun returning to the main island. When I visited, the island conservationists were crossing their fin-
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