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American ginseng Panax quinquefolius L.: A understory herb with quite
a story
Emily H. Mooney
What does it look like? Where does it grow?
American ginseng, Panax quinquefolius L. Araliacae, is rare, medicinal
plant actively harvested from the wild across its range in North America.
It typically grows beneath mixed-hardwoods in 
moist,
well-drained slopes and in particularly lush sites. American ginseng grows
to about 20 inches in height at maturity and has 1 to 5 palmately compound
leaves emanating from a sympodium or stalk. Its glossy-green leaves and
sympodium arise from an underground root in late spring; wild ginseng
collectors seek this thickened, multi-branching root, the harvest of which
kills the entire plant. About mid-June, most plants over three years produce
a cluster of tiny white flowers in the center of the whorl of leaves.
The flowers produce a hard-seeded fruit, which turns a distinctive red
in the fall.
American Ginseng's Rich History
Almost every indigenous culture that existedin American ginseng's natural
range used it in their materia medica (Bodin 1999). The
Iroquois called it 'garent ogeun,' which translates roughly as 'man root'
for its branching root that roughly resembles the human form (Bodin 1999).
Interestingly, the Chinese' name for their native Panax ginseng species
is 'jin-cheng', which also translates as 'man root' (Bodin 1999). The
Chinese consider ginseng to be a true panacea--a drug with the ability
to cure anyailment; in fact, the genus name, Panax, is derived from this
belief. The Chinese have valued the root of their Panax ginseng L. for
centuries, such that truly wild ginseng became nearly extinct. Beginning
in the 18th century, the d
emand
for wild ginseng root found a new source in North America as Panax quinquefolius
was substituted for Panax ginseng.
The export of American ginseng dates to the early 1700's when a French
Jesuit in China sent a description of the morphology, habitat and the
medicinal use of Chinese ginseng to a fellow priest in Canada (Carlson
1986). After searching the woods around Montreal, Father Joseph Francis
Lafitau found what became known as American ginseng thriving in the understory
(Carlson 1986). The first speculative boatload of root soon followed Lafitau's
discovery; it brought an unheard-of $5 a pound, which set off a steady
trade of the plant between the two continents (Bourne 2000).
The Status of American Ginseng Today
As centuries of continuous harvest and export of American ginseng reduced
wild populations, methods of cultivating American ginseng were developed
(Carlson 1986). Though cultivation of American ginseng has been successful,
the demand for wild roots has not diminished. The gnarled, many-branching
wild roots are considered more potent in Chinese medicine, and are thus
considerably more valuable than cultivated roots (Robbins 2000). The volume
of wild
roots legally harvested per year in the U.S. averages 58 metric tons (128,000
pounds), an equivalent of over 85 million plants (Robbins 2000).
In 1973, the Convention on International trade in Endangered Species of
Wild Fauna and Flora (CITES) called for the protection of American ginseng
because the demand for roots could potentially threaten the survival of
the species (Robbins 2000). The U.S. Fish & Wildlife Service now oversees
the trade of American ginseng and gives approval for export to states
where it can be shown that harvesting will not endanger the species and
that plants are being legally collected (Robbins 2000). Conservation policy
recently became stricter because of mounting evidence of a lower U.S.
harvest and illegal poaching from parks (Robbins 2000).
My research
American ginseng is a plant at the crossroads of two endangering factors:
habitat destruction and over-harvesting (Lewis 1988). To gain perspective
on these forces, I studied three naturally occurring populations of P.quinquefolius
in Onondaga County, N.Y. My efforts included a detailed inventory of the
plants, which meant measuring various reproductive & vegetative traits.
In addition, I recorded features of the habitat where the populations
occurred, including overstory vegetation and apparent site history.
In another part of my research, I sought to evaluate the possibility of
re-introducing American ginseng to New York forests. For the reintroduction,
two sites were s
elected
on SUNY ESF property in Onondaga and Cortland counties in New York. One
site is a forest re-grown in the last 75 years from pasturage; it borders
an interstate highway and residential housing just outside the city of
Syracuse. The other site I located inside an expansive forest in the remote
hills of rural New York. In 2 replicate 10-square-meter plots, I randomly
planted both 1 year-old rootlets and 2 year-old potted plants bought from
a commercial nursery. The success of the transplants was measured as the
growth and maintenance of an aboveground stem and leaves over the growing
season.
Results
After extensive searches through out Onondaga County, I was able to locate
three populations of P.q
uinquefolius
in the protected area and in neighboring private land. Each of the populations
contained plants in three vegetative stages: 1-leaved plants of 1 to 3
years-of-age, 2-leaved plants of 3+ years-of-age and 3-leaved plants of
approximately 7+ years-of-age (Charron & Gagnon 1991). No plants with
four or greater
leaves were found. I also recorded the reproductive status of each of
the populations by counting the number of flowers and fruits on each plant.
Population 3, with the fewest plants, achieved the highest reproductive
capacity. Population 3 also contained the largest plants. The three populations
occurred in distinct habitats, which consisted of unique mixtures of overstory
and understory vegetation.
The survivorship of the both the plants and rootlets was low in both 
sites.
The plants exhibited evidence of several common diseases when they were
fresh from the nursery. Once the plants were in the ground, they were
subject to intense herbivory: I consistently found slugs on the damaged
plants, or in most other cases the additional damage appeared to be of
insect origin.
Discussion
The three populations of American ginseng occur on the ridge tops and
slopes of a single stream valley in central New York, yet display distinct
differences in vegetative and reproductive traits from one another. Three
distinct site histories also appear, which seem to relate to the differences
I observed in the P.quinquefolius plants. For example, population 3 produced
the highest number of fruits and flowers, largest leaflets and the tallest
sympodiums on average. All together, population 3 contains the healthiest,
most successful plants (Lewis 1984). The observed differences in age structure
between the populations do not sufficiently account for these variations.
Population 1 actually has more, older plants but has a smaller reproductive
output than population 3. Relating these traits to site conditions, population
3 occurs beneath a mature overstory of trees like red maple, Acer rubrum,
a typical climax species in the region. Conversely, sites 1 & 2 occur
on sites where stumps and shade intolerant trees provide evidence of rece
nt
logging and disturbance. Populations 1 & 2 were able to survive or
establish themselves in an altered forest, but contain smaller, less reproductive
plants. Based on my observations, the impact of habitat destruction or
degradation appears to be a reduction in the reproductive and vegetative
output of American ginseng.
Because of many other mitigating factors, especially the poor condition
of the plants from the nursery, I hesitate to extrapolate much meaning
from the reintroduction study. American ginseng seedlings typically exhibit
high mortality in their first three years; so the low survival rates may
not necessarily indicate site quality. In addition, some of the plants
that I have considered to have 'failed' may have gone into dormancy. A
complete study of the viability of re-introducing American ginseng would
definitely exceed a single growing season, but is something I would like
to continue to pursue.
Ginseng Reintroduction Resource Page
Medicinal Plant Conservation Resources on the Web
About the author: Emily H. Mooney
Currently pursuing a B.S. at SUNY-ESF in Environmental & Forest Biology.
My fascination with medicinal plants and their ecology will continue at
a yet-to-be named graduate school.
References
Bodin, Madeline. 1999. The ginseng hunters.
Northern Woodlands. Autumn: 14-18.
Bourne, Joel. 2000. On the trail of the 'sang poachers.
Audubon March-April: 84-91.
Charron, Danielle and Daniel Gagnon. 1991. The demography of northern populations of Panax quinquefolium (American ginseng). 79, 431-445.
Carlson, Alvar W. 1986. Ginseng: America's Botainical Drug connection to the Orient. Economic Botany. 40 (2): 233-249.
Hufford, Mary. 1997. American ginseng and the culture of the commons.
Orion 16: 11-14
Lewis, Walter H. 1988 Regrowth of a decimated population of Panax quinquefolium in a Missouri Climax forest. Rhodora 90:1-5
------------------- 1984. Population structure and environmental corollaries of Panax quinquefolium in Delaware County, New York. Rhodora 86: 431-438
Robbins, Christopher S. 2000. Comparative analysis of Management regimes
and Medicinal Plant Trade Monitoring Mechanisms for American ginseng and
Goldenseal. Conservation Biology 14:1422-1434
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