Chapter 15
Risks Associated with Overcollection
of Medicinal Plants in Natural Habitats
Maureen McKenzie, Ara Kirakosyan, and Peter B. Kaufman
Abstract Human exploitation of fragile plant communities and ecosystems has
been occurring in recent times at an accelerating pace. In general, worldwide loss of
habitat has resulted from human overpopulation, global warming, resource extrac-
tion, creeping agricultural developments (especially on marginal lands), extensive
use of herbicides (as in Vietnam), construction of highways, desertification, fire,
flooding/tsunamis, alien invasive species, and disease/insect attacks. This is hap-
pening in tropical rain forests worldwide due, in particular, to habitat destruction
from mining, removal of forest trees through cutting and the use of fire, livestock
overgrazing, and farming. In temperate regions the predominant causes are clear-
cutting of forests, collecting wood from trees and shrubs for fuel, overgrazing by
livestock, mining, damming river systems, and allowing urban sprawl to replace
forest ecosystems. In Arctic regions, ecosystem destruction is the result of massive
clear-cuts of boreal forests for pulpwood for paper manufacture, lumber, and wood
products.
The Worldwatch Institute in Washington, D.C. has successfully documented these
calamities over the past two decades. Unfortunately, their prognosis is not good for
the future regarding the Earth’s natural resources. Humans, with their burgeoning
populations, continue to be engaged, despite sufficient warning, in overly exploitive
activities that squander natural products that occur in vast ecosystems. As a result,
the population is living way beyond the carrying capacity in many regions of the
planet.
The purpose of this chapter is to point out ways which might reverse this trend.
Critical considerations involve preserving natural and wilderness areas; commit-
ment to sustainable harvesting of plants in these ecosystems; saving rare, threatened,
and endangered species of plants in “gene banks,” seed banks, tissue culture banks,
nurseries, botanical gardens and arboreta, and parks and shrines; and cultivating
plants in an ecologically friendly way. Following these strategies, the supply of nat-

population.
• Critically endangered: faces an extremely high risk of extinction in the immediate
future.
• Endangered: faces a very high risk of extinction in the near future.
• Vulnerable: faces a high risk of extinction in the medium term.
• Least concern: no immediate threat to the survival of the species.
The Botanic Gardens Conservation International (BGCI), which represents botanic
gardens in 120 countries, stated that “400 medicinal plants are at risk of extinction,
from over-collection and deforestation, threatening the discovery of future cures for
disease.” (BGCI, January 18, 2008). The most notable are Yew trees (Taxus spp.)
(from which the bark is used for the cancer drug, paclitaxel); Hoodia gordonii Sweet
ex Decne. (a source of weight loss supplements from Namibia); half of Magnolia
spp. (used as Chinese medicine for 5,000 years to fight cancer, dementia, and heart
disease); and Autumn crocus (Colchicum autumnale L. prescribed for gout). The
group also found that 5 billion people benefit from traditional plant-based medicine
for health care.
Many medicinal plants have been overcollected almost to the point of extinc-
tion in their natural habitats. In the United States, notable examples include
Pacific yew (Taxus brevifolia Nutt.), ginseng (Panax ginseng C.A. Mey.), gold-
enseal (Hydrastis canadensis L.), black cohosh (Cimicifuga racemosa (L.) Nutt.
or Caulophyllum thalictroides (L.) Michx.), American ginseng (Panax quinque-
folius L.), bloodroot (Sanguinaria canadensis L.), prairie coneflower or echinacea
(Echinacea spp.), helonias root (Chamaelirium luteum (L.) A. Gray), kava kava
15 Risks Associated with Overcollection of Medicinal Plants 365
(Piper methysticum G. Forst.; Hawaii only), lady’s slipper orchid (Cypripedium
spp.), Lomatium (Lomatium dissectum (Nutt.) Mathias & Constance), osha (Ligus-
ticum porteri J.M. Coult. & Rose), partridge berry (Mitchella repens L.), peyote or
mescal button (Lophophora williamsii (Lem. ex Salm-Dyck) J.M. Coult.), slippery
elm (Ulmus rubra Muhl.), sundew (Drosera spp.), trillium (Trillium spp.), true uni-
corn (Aletris farinosa L.), Venus’ flytrap (Dionaea muscipula J. Ellis), and wild yam

but citizen action groups, such as the National Parks and Conservation Associa-
tion,theSierra Club,theNature Conservancy,theWilderness Society,theNatural
366 M. McKenzie et al.
Resources Defense Fund, and the many other organizations who operate in the indi-
vidual states, must be ever vigilant and ready for concerted action.
Sustainable Biopreserves for Indigenous Peoples: Based on a recent United
Nations Conference on Environment and Development (UNCED), the United States
has placed forest management and protection as a priority of UNCED. Further, dis-
cussions by the US government agencies and nongovernmental organizations have
concluded that a provision needs to be included on the needs of indigenous peo-
ples who use the forests for their livelihood, social organization, or cultural identity,
and who have an economic stake in sustainable forest use (Plotkin and Famolare,
1992). Actions include promoting means for indigenous peoples and members of
local communities to actively participate in decision-making processes for any pro-
posed forest-related actions where their interests are affected (Plotkin and Famolare,
1992). Other propositions are to identify ways to enhance the value of standing
forests through policy reform, more accurately reflecting the costs and benefits of
alternative forestry activities, in addition to identifying economically valuable forest
species, including timber and nontimber species, and the development of improved
and sustainable extraction methods (Moran, 1992).
Nabhan (1992) has indicated that the following criteria offer the best guidelines
for ensuring that indigenous peoples and other peasant communities benefit from
applied ethnobotanical development, and that projects sustain rather than deplete or
destroy biodiversity.
• The project should attempt to improve the objective and subjective well-being
of local communities rather than seeking cheap production sites and importing
inexpensive labor.
• Cultivation in fields or agroforestry management should be considered if there
are threats that wild harvests will deplete the resource.
• Wildland management and sensitive harvesting practices should be introduced

pany them during their stay. The Kuna control access to sites and require reports on
all research. These terms allow the Kuna to patrol and protect outlying areas while
learning from the scientists.
Head and Heismann (1990) in Lessons of the Rainforest, tell about the organiza-
tion called Environmental Restoration in Southern Colombia (CRIC). It is composed
of 56 Indian communities that are organized to protect Indian lands, resources, cul-
ture, and rights in an area where the forest has been destroyed by mines and cattle
ranches. CRIC began a forestry program with three tree nurseries which provided
seedlings to those communities that agree to plant a minimum of 1000 trees of native
species. To date, one community has completed nine reforestation programs.
15.2.2.1 The Nature Conservancy
The main objective of the Nature Conservancy is to protect plants, animals, and
ecological communities that represent biodiversity. To do this, they rely on conser-
vation science to guide its work. Conservation science programs encompass biolog-
ical, ecological, and technological knowledge that are used to identify and protect
sensitive biodiversity, and in management methods and practices used to ensure its
survival. The Natural Heritage Program and the Conservation Data Center Network
programs collectively track in their databases the protected status and locations or
rare and endangered species and ecological communities. Over the last four decades,
the Nature Conservancy has protected more than 8.1 million acres (3.28 million ha)
of habitat based on information about the location, range, and status of rare species.
This number is even higher for total acreage protected to date: it is 9.3 million acres
(3.77 million ha) of land in the United States and 40 million acres (16.19 million
ha) throughout Latin America, the Carribean, and the Asia/Pacific regions. Indeed,
it operates the largest system of privately owned nature preserves in the world.
In carrying out its work, the Nature Conservancy addresses ecological function
and influences of people and develop better conservation planning methods and
tools that will allow planning across immense biologically defined regions and the
368 M. McKenzie et al.
range of a particular ecological community. Stewardship of land and its resources

tainable forest management. In Madagascar, the WWF brokered a debt-for-nature
swap which has trained more than 350 local conservation agents and created a net-
work of locally managed tree plantations. It is also helping to develop alternatives
to cattle production and slash-and-burn agriculture in order to protect native forests
(World Wildlife Fund, 1995).
15.2.2.3 The Sierra Club
The Sierra Club was founded by John Muir in 1892 in San Francisco, California, to
help preserve the pristine beauty of the Sierra Nevada mountain range in California.
Today, it is a national organization with chapters throughout the United States.
It continues to expand, stop abuse of wilderness lands, save endangered species,
15 Risks Associated with Overcollection of Medicinal Plants 369
and protect the global environment. It helps to create and enlarge national parks,
preserve forests, designate wilderness areas, halt dams, and prevent destruction of
priceless habitats. The Sierra Club helped save Alaska’s Arctic National Wildlife
Refuge from imprudent utilization by oil companies, establish National Park and
Wilderness Preservation Systems, and safeguard more than 132 million acres of
public land.
This organization launched the Critical Ecosystems Program, which is designed
to protect and restore 21 regional ecosystems in the United States and Canada. This
program is involved in designing protection for public and private lands that are
the core habitats for native species. It established task forces for each ecoregion,
drawing together activists with expertise in various areas to develop strategies to
save those regions. What are these strategies for the different ecoregions?
• Atlantic Coast and Great Northern Forest – preserve biodiversity by restoring and
sustaining habitat for the full array of native plants and animals, establish sound
forestry policy, and preserve wilderness.
• Central Appalachia, Southern Appalachian Highlands, and American Southeast –
saving from development, as much as possible, the shoreline stretching 2000
miles (3200 km) from Florida to the mouth of the Rio Grand River.
• Interior Highlands, Great Lakes, Great North American Prairie – establish a sys-

Garden in St. Louis, MO. This center is dedicated to conserving rare plants native
to the United States in an integrated plant conservation context through a collabo-
rative program of ex situ plant conservation, research, and education. It is made up
of a consortium of 25 botanical gardens and arboreta (Center for Plant Conserva-
tion, 1996). A national survey by the CPC in 1988 found that over three-quarters of
the endangered flora of the United States is in six areas: Hawaii, California, Texas,
Florida, Puerto Rico, and the Virgin Islands. It has designated these areas as con-
servation priority regions. The CPC Priority Regions Program addresses the need
for conservation through programs of land conservation, management, offsite col-
lection in seed banks, botanical gardens and other institutions, research, and site
surveys (Center for Plant Conservation, 1996). The National Collection of Endan-
gered Plants contains seeds, cuttings, and whole plants of 496 rare plant species
native to the United States. The collection is stored at 25 gardens and arboreta that
form part of the CPC.
The Royal Botanic Gardens at Kew, United Kingdom, support six ex situ and
in situ conservation projects. The activities range from acting as the UK Scientific
Authority for Plants for CITES (Convention on International Trade in Endangered
Species of Wild Fauna and Flora), cooperating in the recovery and reintroduction of
endangered species, and in production of management plans for sustainable devel-
opment and protected areas (Royal Botanic Gardens, Kew, 1996b).
The Wrigley Memorial and Botanical Gardens at Catalina Island, CA, is still
another example. The garden places its emphasis on California island endemic
plants. Many of these plants are extremely rare, with some listed on the Endangered
Species List.
15.2.4 Plant Tissue Culture as a Method to Clone and Rescue
Rare and Endangered Plant Species
Plant tissue culture has been the primary method used to rescue rare and endangered
plant species and to increase their numbers of genetically similar offspring. It is a
practice used to propagate plants under sterile conditions, often to produce clones
of a plant. The most useful plant tissue culture protocols involve shoot-tip cul-

faces (and sometimes interiors) with microorganisms, so surface sterilization in
chemical solutions (usually alcohol or bleach) is required of starting materials. The
tissue which is obtained from the plant to start the culture is called an explant.
Explants are then usually placed on the surface of a solid culture medium, but are
sometimes placed directly into a liquid medium, particularly when cell suspension
cultures are desired. Solid and liquid media are generally composed of inorganic
salts plus a few organic nutrients, vitamins, and plant hormones. Solid media are pre-
pared from liquid media with the addition of a gelling agent, usually purified agar.
The composition of the medium, particularly the plant hormones and the nitrogen
source (nitrate versus ammonium salts or amino acids), has profound effects on the
morphology of the tissues that grow from the initial explant. For example, an excess
of auxin will often result in a proliferation of roots, while an excess of cytokinin
may yield shoots. A balance of both auxin and cytokinin will often produce an
unorganized growth of cells or callus, but the morphology of the outgrowth will
depend on the plant species as well as the medium composition. As cultures grow,
pieces are typically sliced off and transferred to new media (subcultured) to allow
for growth or to alter the morphology of the culture. As shoots emerge from a culture
(Fig. 15.1), they may be sliced off and rooted with auxin to produce plantlets which,
372 M. McKenzie et al.
a
b
Fig. 15.1 In vitro shoot (a)
and callus (b)culturesof
Hypericum perforatum L.
when mature, can be transferred to potting soil for further growth as normal plants
in the greenhouse.
The skill and experience of the tissue culturist are important in judging which
pieces to culture and which to discard. Based on work with certain model systems,
particularly tobacco, it has often been claimed that a totipotent explant can be grown
from any part of the plant. However, this concept has been vitiated in practice. In