National Geographic - UK (2022-05)

(Maropa) #1
PHOTOS (CLOCKWISE FROM TOP): ZOONAR GMBH/ALAMY STOCK PHOTO; CHRISTIAN MOHR; DEBORAH ROSE

Saving Seeds, by More Means
An estimated 8 percent of plant species—
including about a third of endangered and
vulnerable ones—have recalcitrant seeds
that won’t tolerate drying, says a study in
the journal Nature Plants. That means typical
seed bank processes won’t work for those
species, so experts urge additional measures,
such as cryopreservation, to guard against
their extinction. —HICKS WOGAN

A SURVEYING SLIPUP 140 YEARS AGO spared a patch of old-growth
pine forest in northern Minnesota from the saws and axes of the
region’s logging boom. Now the trees —the kind that once filled the
area’s famed North Woods—are estimated at up to 400 years old.
Most of the region’s forests may look mature, but many trees are
less than a century old; settlers and lumber barons clear-cut much
of the forest between the 1890s and 1920s. So how were more than
30 acres of old-growth pines missed? According to U.S. government
records, in the winter of 1882, four surveyors headed into the thick
forests to inventory land features. Cold and living roughly, they
apparently rushed the job and made a mistake, categorizing as a
lake the area that was actually forest acreage. Later, when loggers
were bidding on that land, it was listed as being underwater and
so was not pursued for logging rights.
That’s a boon to modern-day hikers. They can wander through
what’s now called the Lost 40 and gaze up at the towering pines—
one of which is the state’s largest living red pine at 120 feet tall and
nearly 10 feet around. —KATIE THORNTON

CENTURIES-OLD SURVIVORS


IN THE LATE 180 0 S AND EARLY 1900 S, LOGGERS
CLEAR-CUT PINES IN MINNESOTA’S NORTH WOODS—
BUT SOME REMAIN, THANKS TO A MAPPING ERROR.

From trees,
a new way
to pinpoint
earthquakes
In Chile after a
magnitude 8.8
earthquake, a team
of scientists from
U.S. and German
research institu-
tions noticed that
streams in their
valley work site
had sped up. It’s
known that earth-
quakes make soil
more permeable
and increase the
downhill flow of
groundwater.
When the
researchers later
took core samples
from pine trees in
valleys and along
ridges in a Chilean
mountain range,
measures of the
tree rings’ cells
(left) confirmed
that valley trees
with extra water
after the earth-
quake had seen
temporary growth
spurts and that
higher, drier trees
had grown more
slowly. In this way,
the earthquake
had left an imprint
on trees.
The research-
ers also have made
a mark: The tree-
ring technique can
potentially date
a seismic event to
within weeks of its
occurrence, more
precise than the
usual metric, the
nearest year. —HW

DISPATCHES
FROM THE FRONT LINES
OF SCIENCE
AND INNOVATION

BREAKTHROUGHS (^) | EXPLORE
On this confocal
laser scanning
image of cells
from a pine
in the Chilean
earthquake
zone, the orange
outline shows
roughly the
quake time span;
afterward, extra
water caused
growth spurts
that affected
tree-ring growth.

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