About 4,000 plants native to the United
States are of concern to conservationists. The following list profiles
just a few of these plants.
- The Tennessee coneflower (Echinacea tennesseensis)
is known from only 10 cedar glades, all within 15 miles of Nashville,
Tennessee. The expansion of the Nashville metropolitan area poses the
most serious threat to this species. In addition, interbreeding or hybridization
with other coneflower species may jeopardize this coneflowers's survival
as a distinct species.
- The cockspur (Erythrina eggersii) has been reduced
to just four locations on St. John in the U.S. Virgin Islands and one
or two sites on Puerto Rico. Fewer than 75 plants still grow in the
wild. The U.S. Virgin Islands and Puerto Rico constitute one of the
five CPC "priority regions" because of their high percentage
of rare native plants.
- The green pitcher plant (Sarracenia oreophila) is
a federally protected endangered species that is now limited to a few
wild populations in northeast Alabama and adjacent Georgia. The very
limited range and specialized habitat of this species make it the rarest
of all pitcher plants. Pitcher plants are unusual because they are carnivorous,
obtaining nutrients from insects and other invertebrates that get trapped
inside them. Unfortunately, this interesting trait makes them a prime
target for plant collectors.
- The Ma`o, or Hawaiian cotton (Gossypium tomentosum),
has been so reduced by seaside development and habitat destruction that
it is now vulnerable to extinction. This plant was once used by Hawaiians
to produce green and yellow dyes for cloth. Although Hawaiian cotton
is not suitable for weaving, it has been used by the cotton industry
in developing disease-resistant strains of commercial cotton.
- The California Orcutt grass (Orcuttia californica)
is endemic to vernal pools of southern California. These seasonal wetlands
fill with water after fall and winter rains and dry out during the spring
and summer. Vernal pools are unique and fragile ecosystems, and they
are being rapidly destroyed by urban and agricultural development, mowing
and livestock grazing, and off-road vehicles.
- Price's groundnut (Apios priceana) was once used as
a source of food by native Americans, and if recovery efforts are successful,
this vine could be developed as a food crop in the United States. Unfortunately,
only 25 populations still grow in the Midwest, and many of these consist
of just a few plants. Threats include trampling and grazing by cattle,
clearcutting, competition from exotic species, and herbicides.
Plants in Peril table