The sixth in a series on NSF's Long Term Research in Environmental Biology (LTREB) award.

2. Facing a panoply of threats
First, he says, there's harvesting for medicinal uses, "which
is widespread and often illegally or at least unethically
done. Then we have our four-footed friends--white-tailed
deer--which eat a significant number of plants every year."
The plants' next challenge is the growth of invasive species
such as multiflora rose and garlic mustard, which compete
with ginseng. The effects of global warming, including
summers with heat waves and droughts, add to the burden
for these plants of cooler climes. "Ginseng is also affected
by ice storms, late frosts and hurricane flooding," says
McGraw.
Then these Indiana Joneses of the plant world must survive
what McGraw refers to as "natural pests:" insects
defoliators and fungal pathogens. Last--but definitely not
least--is us.
"We're just beginning to understand what humans are
doing to the forests where ginseng thrives: timbering,
suppressing natural fires, mining, clearing land for housing
developments, the list goes on and on," says McGraw. The
persistence of a slow-growing and valuable medicinal plant
"despite all this," he says, "is a testament to the resilience
of nature--and to the stewardship of those land-owners
who care about protecting biodiversity in their forests."
“The sixth in a series on NSF's Long
Term Research in Environmental
Biology (LTREB) award” –
(NFS.GOV)
Environmental facts: http://goo.gl/C2OTZ
http://goo.gl/xjCoA

3. Tigers, elephants and ginseng all share a common
feature, says Saran Twombly, director of NSF's LTREB
program. "These dwindling populations face increasing
threats that trap them in an extinction vortex,"
Twombly says. "McGraw's research relies on long-term
data to identify the factors threatening populations of
this important forest plant. The results show the knife-
edge that separates healthy and unhealthy
populations." The NSF LTREB award "has been critical to
our understanding of the 'big picture' of ginseng
conservation," says McGraw.
He and colleagues work on one species of ginseng,
Panax quinquefolius L., American ginseng. This member
of the ginseng family, whose genus name Panax means
"all heal" in Greek, hides deep in eastern deciduous
woodlands.
The plant was historically found in rich, cool hardwood
forests--from southern Quebec and Ontario south to
northern Georgia, and west as far as Minnesota,
eastern Oklahoma and northern Louisiana. "Ginseng
populations vary from frequent to uncommon to rare
across the landscape," says McGraw, "but they're
almost always small, usually fewer than 300 plants."
The species has long been valued for its medicinal
qualities, especially by Asian cultures. They've
integrated American ginseng into traditional
medicinal practices as a complement to native Asian
ginseng species. In Asia, ginseng is considered an
adaptogen--it enhances overall energy levels. "In
western medicine, ginseng has exhibited anti-cancer
properties in cell cultures," says McGraw. "It's also
shown beneficial effects on blood sugar and obesity,
as well as on enhancing the immune system for
prevention of colds and flu." After ginseng was
discovered in North America, the market quickly
became profitable enough to fuel intense wild
harvesting, eventually reaching an industrial scale.
"Ginseng shares a part of early American history,"
says McGraw. "Its roots--the most sought-after
parts--were first exported to Asia from the United
States in the early 1700s." In one typical year (1841),
more than 290,000 kilograms of dry ginseng roots
were shipped from North America to the Asian
continent. "Although average root size was larger in
the 1800s than it is today," says McGraw, "even a
conservative estimate suggests that this represents
at least 64 million roots."

4. Sustainability and ginseng: McGraw and colleagues' research shows that ginseng
harvesters willing to employ a stewardship strategy gain the most benefit by
harvesting when seeds are ripe, usually in autumn months, then planting the seeds
to ensure high germination rates. September is a summertime away. But in
northeastern forests, ginseng leaves have already unfurled.
By three centuries later, northeastern forests may be empty--at least of an
unassuming and "all healing" herb named ginseng.
Ginseng at the forefront: Harvest of the plant has continued
apace, he says, particularly in the Appalachian region, where the
sale of ginseng still supplements household incomes. Ecologists
began studying ginseng because of its value as a wild-harvested
species, and its decrease in abundance after decades of
harvesting. Now, however, ginseng has become an important
model species--a sensitive indicator of the effects of global and
regional environmental change on deciduous forests.
Most states with ginseng populations are converging on a
uniform start date for harvesting--Sept. 1. "That allows time after
harvest for planting ripe seeds that will lead to recovery of the
plants," McGraw says. Since forests are, for the most part, open
to everyone, ginseng will continue to be harvested as long as
there is immediate profit to be made, scientists believe.
Successful sustainability in such open access habitats, they say,
depends on management of the resource by those who actively
harvest it.