PHOTOS: REBECCA CAIRNS-WICKS (TOP LEFT); SELECTPHOTO/ALAMY STOCK PHOTO; CHRIS JOHNS (RIGHT)EXPLORE | PLANT EXTINCTION
WEAKENING LIFE’S
GREEN FOUNDATION
Lost and Found
Top: Botanists tried to
save the St. Helena olive,
but in 2003, fungi wiped
out the few surviving
seedlings and cuttings.
Bottom: Gardeners’
demand for the Chilean
crocus nearly drove it
extinct in the wild by the
1950s. But in 2001, a thriv-
ing population was found
on land south of Santiago.Plants anchor
our planet’s
ecosystems but
hundreds have
gone extinct—
with unclear
consequences.WHEN YOU CONJURE up “extinction” in
your mind’s eye, you probably see an
animal—a dodo, perhaps, or a Tasma-
nian tiger. But the biodiversity crisis
isn’t just faunal, it’s floral too. Since the
1750s, at least 571 species of plants have
gone extinct in the wild, according to
a global survey recently published in
Nature Ecology & Evolution.
More than eight plant species have
disappeared every three years, on aver-
age, since 1900. This pace of extinction
is as much as 500 times plants’ natural
or background extinction rate.
“I find it shocking on a personal
level, but bigger than that, I find
it frightening for the future of our
planet,” says study co-author Maria
Vorontsova, a plant taxonomist at
the U.K.’s Royal Botanic Gardens,
Kew. “Plants are the infrastructure of
ecosystems,” she says, and they’re
“interdependent with other organ-
isms—and with one another—in ways
we don’t completely understand.”
How have human activities pushed
plants to the brink worldwide? Some
species, such as the St. Helena olive
(Nesiota elliptica), were confined to
tiny ranges. Settlers on the South
Atlantic island of St. Helena cleared
much of the vegetation, eroding the
tree’s habitat; the last wild individual
died in 1994. Others were poorly known
from would-be farmland or urban
areas. In 1912 botany student Norma
Pfeiffer was walking along Chicago’s
Torrence Avenue when she discovered
Thismia americana, a bizarre, leafless
plant related to “fairy lanterns” in Aus-
tralia and New Zealand. It hasn’t been
seen since 1916, despite many searches.
The study’s count of extinct plants is
almost certainly an underestimate, but
seedlings of hope persist. The authors
also note that 431 plants once thought
extinct, such as the Chilean crocus
(Tecophilaea cyanocrocus), have been
rediscovered. Keeping these plants
with us will be no small feat: Some
89 percent of them are still at risk of
extinction. —MICHAEL GRESHKOBotanists on Kauai have
been collecting threatened
plants since the late 1980s:
Here Kenneth Wood (holding
a plant in his mouth) and col-
league Steve Perlman dangle
from the side of a cliff above
Kauai’s Kalalau Valley to col-
lect specimens. Despite such
efforts, the extinction rate of
the plants is accelerating.32