The
Greenbrier River Watershed Assessment
Threatened, Endangered, and
Sensitive Plants
Four federally-listed threatened and endangered plant species are
known to occur on the Monongahela National Forest: running buffalo clover (Trifolium
stoloniferum), shale barren rockcress (Arabis serotina), Virginia
spirea (Spiraea virginiana), and small whorled pogonia (Isotria
medeoloides). Sixty-one plant species are listed as Regional
Forester’s Sensitive Species (RFSS) on the Forest.
Threatened and Endangered Plants
Two of the four threatened and endangered species are known to
occur within the Greenbrier River Watershed. Potential habitat may occur
for the other two species.
Virginia Spirea
- Virginia spirea is a clonal shrub found on damp, rocky banks of
large, high-gradient streams. The shrub may be found in either full sun or
shade. Within the watershed, potential habitat for Virginia spirea is
limited to the channels and banks of large streams. Elevation range for known
occurrences in West Virginia is 1000 to 1800 feet. The only known occurrence on
the Forest consists of two subpopulations along the Greenbrier River at the
southern edge of the White Sulphur District.
Running Buffalo
Clover - Potential habitat for running buffalo clover typically exists in
lightly disturbed forests and woodlands on soils derived from circumneutral
geologic features. The Monongahela National Forest is a stronghold for
running buffalo clover, with the largest and highest quality populations
range-wide occurring on the Forest. Most of the Forest’s populations are
associated with old skid trails, lightly used roads, or other features that
cause moderate soil disturbance. Potential habitat in the
Greenbrier River Watershed is likely concentrated in areas of favorable geology
and past soil disturbance. Existing records show occurrences of running
buffalo clover within the watershed.
Small Whorled
Pogonia - Habitat preferences for small whorled pogonia are poorly known,
but could include a variety of forested habitats. The available
literature indicates occurrence in mixed deciduous and pine-hardwood habitats
of a variety of ages, often near partial canopy openings. Likelihood of
occurrence for small whorled pogonia is considered low because it is not known
to occur within the watershed. However, potential occurrence cannot be
completely ruled out based on habitat preferences and due to the difficulty of
locating this species using conventional survey techniques.
Shale barren
Rockcress - Shale barren rockcress is not likely to occur within the
watershed due to lack of shale barren habitat. Shale barrens are limited
to the drier areas on the eastern side of the Forest.
Regional
Forester’s Sensitive Plants
Three of the 61 RFSS plants are known to occur within the
Greenbrier River Watershed: Appalachian blue violet (Viola appalachiensis),
butternut (Juglans cinerea), and rock skullcap (Scutellaria saxatilis).
Potential habitat could occur for 30 additional RFSS plants. The total
for potential and known RFSS plants in the watershed is 33 species. RFSS
plants have been grouped according to their primary habitat - wetland/riparian
habitat, mesic/cove forest, and rocky habitat.
Known or
Potential Wetland and Riparian Habitat RFSS Plants in the Greenbrier River
Watershed
|
Scientific
Name
|
Common
Name
|
Habitat
Comments
|
|
Baptisia australis var.
australis
|
Blue wild indigo
|
Primarily early successional wetlands
|
|
Botrychium oneidense
|
Blunt-lobed grapefern
|
Wooded wetlands
|
|
Euphorbia purpurea
|
Darlington’s spurge
|
Open or closed canopy
|
|
Hasteola suaveolens
|
Sweet-scented Indian plantain
|
Riverbanks and disturbed wetlands
|
|
Hypericum mitchellianum
|
Blue Ridge St. John’s wort
|
Riverbanks and disturbed wetlands
|
|
Ilex collina
|
Long-stalked holly
|
Open or closed canopy
|
|
Juncus filiformis
|
Thread rush
|
Open canopy
|
|
Marshallia grandiflora
|
Large-flowered Barbara’s buttons
|
Flood-scoured stream banks in full sun
|
|
Menyanthes trifoliata
|
Bog buckbean
|
Bogs
|
|
Pedicularis lanceolata
|
Swamp lousewort
|
May prefer circumneutral soil
|
|
Poa paludigena
|
Bog bluegrass
|
Sun to partial shade
|
|
Polemonium vanbruntiae
|
Jacob’s ladder
|
Swamps, bogs, riparian zones
|
|
Potamogeton tennesseensis
|
Tennessee pondweed
|
Standing or slow-flowing water
|
|
Taxus canadensis
|
Canada yew
|
Occurs in spruce forests, or in riparian areas or wetlands in
lower elevations.
|
|
Vitis rupestris
|
Sand grape
|
River banks and washes
|
|
Woodwardia areolata
|
Netted chain fern
|
Swamps and wet woods
|
Known and
Potential Mesic Forest and Cove Habitat RFSS Plants in the Greenbrier River Watershed
|
Scientific
Name
|
Common
Name
|
Habitat
Comments
|
|
Botrychium lanceolatum var.
angustisegmentum
|
Lance-leaf grapefern
|
Moist, shady woods and swamp margins
|
|
Corallorhiza bentleyi
|
Bentley’s coral root
|
Habitat preferences poorly understood
|
|
Cypripedium parviflorum var.
parviflorum
|
Small yellow lady’s slipper
|
Moist to wet sites
|
|
Cypripedium reginae
|
Showy lady’s slipper
|
Swamps and woods
|
|
Juglans cinerea
|
Butternut
|
Most likely in rich alluvial soil, but could occur elsewhere
|
|
Triphora trianthophora
|
Nodding pogonia
|
Deep leaf litter or humus
|
|
Viola appalachiensis
|
Appalachian blue violet
|
Often in riparian areas, but can occur in other mesic situations
|
Known and Potential
Rocky Habitat RFSS Plants in the Greenbrier River Watershed
|
Scientific
Name
|
Common
Name
|
Habitat
Comments
|
|
Cornus rugosa
|
Roundleaf dogwood
|
Rocky areas within forests
|
|
Gymnocarpium appalachianum
|
Appalachian oak fern
|
Rocky woods
|
|
Heuchera alba
|
White alumroot
|
Most likely in dry microsites
|
|
Juncus trifidus
|
Highland rush
|
Rock crevices
|
|
Oryzopsis canadensis
|
Canada mountain rice grass
|
Open canopy, sandstone
|
|
Pycnanthemum beadlei
|
Beadle’s mountainmint
|
Open canopy over rocks
|
|
Scutellaria saxatilis
|
Rock skullcap
|
Rocky areas within forests. Also seen in shaded cut banks and
shoulders of infrequently used forest roads.
|
|
Syntrichia ammonsiana
|
Ammon’s tortula
|
Wet, cool microsites
|
|
Taenidia montana
|
Virginia mountain pimpernel
|
Dry outcrops. Typically a shale barren species, but one
occurrence in Tucker County.
|
|
Trichomanes boschianum
|
Appalachian bristle fern
|
Dripping rocks
|
Although
all threatened, endangered, or proposed species on the Forest may not be
individually addressed in the Forest-wide management direction, the Forest is
obligated to provide sufficient habitat to contribute to their survival and
recovery. This obligation is spelled out in more detail in the Endangered
Species Act, Forest Service Manual and Handbook direction, and various recovery
plans, conservation strategies and agreements, and Memoranda of
Understanding. In addition, Section 7 consultation will occur at the
project level for all proposed actions that may affect these species or their
habitat.
Rare plants and their habitats are protected and enhanced
across the Forest through designation and management of Botanical Areas and
Research Natural Areas, and through continued surveys and mitigation for
species on the RFSS list. Rare plants and communities contribute to the
biodiversity of the Forest and region.
Non-native Invasive Plant Species
The role of non-native insects, diseases, and invasive plants as
disturbance factors has increased in the past century due to the introduction
of these pests from other countries. Some of the species known to
influence the structure and pattern of vegetation are discussed below.
The species listed here are not all inclusive of non-native insects, diseases,
and invasive plants that may be present in the Greenbrier River Watershed.
Non-native Insects
Gypsy Moth (Lymantria dispar L.) -
Gypsy moth was introduced from France to the United States in 1869. The
first defoliation outbreak occurred in 1889. A population crash of the gypsy
moth, caused by the fungus Entomophaga maimaiga, has kept the
population under control for many years. High humidity, frequent
periods of rain, and fairly constant temperatures between 14°C to 26° C are
needed for the fungus to germinate and spread. Without these conditions,
increases in the number of gypsy moth egg masses on the Forest may result in a
population build-up, causing defoliation in numerous “hot spots” in the eastern
section of Pocahontas County where oaks predominate. Population increases
do not always cause significant tree mortality in the first year.
However, continued increases in populations, with successive years of
defoliation, may cause extensive tree mortality. A return to a control
program may be necessary to slow the spread of this insect and reduce tree
mortality.
Oak trees (especially of the white oak group) are the preferred
host for this insect pest. Less than 6% of the forest types in the
Greenbrier River Watershed feature oak, and most of those are the mixed and red
oak groups. Therefore, this area is considered to be at relatively low
risk for massive defoliation by gypsy moth caterpillars.
Hemlock Wooly Adelgid (HWA) (Adelges
tsugae) - This sapsucking insect, introduced to the United States from
Asia in 1924, was detected in Pocahontas County in 1993. The insect feeds
on twigs causing the foliage to discolor and drop prematurely.
Defoliation and death usually occurs about 4 years after a tree is
infested. Eastern and Carolina Hemlocks are highly susceptible to this
insect and no resistant trees have been located to this date. However,
several common predators (including the Japanese Ladybug) of the adelgid have
been released and may prove to be an effective control. Severe cold
weather also seems to control HWA. In January, 1985 and the winter of
1993-1994 severe cold weather (-20° to -28° F) greatly reduced HWA
populations. Infestations of HWA are not apparent above the Hudson River
corridor in New York. It appears cold weather may be a limiting factor in
the spread of this insect. The cooler climate of the Greenbrier River Watershed
may help to limit the impact of this exotic pest.
Non-native Diseases
Beech Bark Disease (BBD) - The beech scale
insect (Cryptococcus fasigua), native to Europe, arrived in Nova
Scotia around 1890. By 1932 trees in Maine were dying from BBD. The
disease results when the bark is attacked by the beech scale, then invaded by
fungi, primarily Nectria coccinea var. faginata and
N. galligena which eventually kills or severely injures beech.
Beech trees over 8 inches diameter are more severely affected then smaller
trees. Mortality occurs in about 30% of the trees that are
infected. Up to 90% of the remaining beech trees in a stand become
severely injured and do not produce quality wood. It appears there are
greater disease levels in stands containing hemlock. Hemlock provides
high shade and moisture preferred by the fungi that attack the tree after
infestation by the scale.
The advancing front of the scale is presently in the Greenbrier
River Watershed. Cutting infected and high risk trees would provide an
opportunity to salvage some of the material and improve the health and
diversity of the stand.
Chestnut Blight (Cryphonectria parasitica)
- This fungus (probably introduced through the importation of chestnut trees
from Asia) was first reported in the United States in 1904. Within 50
years the fungus occupied the entire range and had killed 80% of the American
chestnut. Nearly all the remaining live trees were infected with the fungus and
dying. Prior to the infestation, the American chestnut was a major
component of the eastern hardwood forest comprising 25% of all tree species on
over 200 million acres from New England to Georgia. This tree, which once
grew up to 120 ft tall and over 7 ft in diameter, now rarely attains heights
over 30 ft with diameters up to 6 in before the fungus kills the stem.
The process starts over when the tree resprouts. A few resistant trees
have been found. There is hope that sometime in the future the American
chestnut will return, as a valuable timber and wildlife tree, to the eastern
hardwood forest. An opportunity exists to plant disease resistant
chestnut in this area.
Non-native Invasive Plant Species
Non-native invasive plants have been recognized as a major threat
to conservation of native biological diversity. They out-compete native
species and homogenize ecosystems, thereby threatening to destroy the
distinctiveness of communities whose component species evolved in the absence
of these aggressive competitors. They can also degrade forage quality on
range lands, compete with desirable regeneration after timber harvest, and
reduce the diversity of habitat niches available to a wide variety of wildlife
species.
Many non-native invasive plant species are known to occur in the
Greenbrier River Watershed. Of these, garlic mustard (Alliaria petiolata)
and Japanese stiltgrass (Microstegium vimineum) can cause serious
ecological impacts in forested ecosystems because of their ability to tolerate
shade. Additionally, tree of heaven (Ailanthus altissima) could
cause ecological disruption due to its ability to capture canopy gaps in
forests. Currently, all three of these species are closely associated
with roads, skid trails, and landings, indicating that these transportation
features have served as the primary invasion route in the watershed, probably
through transport of seeds by vehicles, horses, ATVs, boots, etc.
Non-native invasive plants that are less shade tolerant—such as multiflora rose
(Rosa multiflora), autumn olive (Elaeagnus umbellate) and
Kentucky 31 fescue (Festuca arundinacea), have been seeded for wildlife
food or facilitated by the disturbed habitat provided by road corridors.
Such species pose less of a threat to the forested ecosystems that predominate
in the watershed, but in some cases they can spread and cause ecosystem
disruption after being released by natural or human-caused disturbance.
Non-native Invasive Plants in the Greenbrier River Watershed
|
Scientific
Name
|
Common
Name
|
|
Alliaria petiolata
|
Garlic mustard
|
|
Ailanthus altissima
|
Tree of heaven
|
|
Microstegium vimineum
|
Japanese stiltgrass
|
|
Vinca minor
|
Periwinkle
|
|
Phalaris arundinacea
|
Reed canary grass
|
|
Festuca arundinacea
|
Kentucky 31 fescue
|
|
Rosa multiflora
|
Multiflora rose
|
An early detection/rapid response strategy is employed to respond
to new occurrences of non-native invasive plants that threaten forest,
non-forest, and aquatic ecosystems. Existing and new occurrences are
prioritized for treatment based on threats to specific resources and ability to
control the species. Native species and desired non-invasive non-native
species are used to revegetate disturbed areas.
Outbreaks and resident populations of native and non-native pests
are controlled to acceptable levels through careful use of pesticides and
integrated pest management. An early detection/ rapid response strategy
is employed by the Forest to respond to new
occurrences of plants, insects, and diseases that threaten forest and
non-forest vegetation. Pesticide treatments achieve management objectives
and pose little or no risk to humans and the environment.
