This document provides information on 14 invasive plant species present in the Rapidan River watershed: Ailanthus altissima, Alliaria petiolata, Ampelopsis brevipedunculata, Celastrus orbiculata, Centaurea biebersteinii, Lespedeza cuneata, Lythrum salicaria, Lonicera japonica, Pueraria montana, Rubus phoenicolasius, Rosa multiflora, Polygonum perfoliatum, Myriophyllum aquaticum, and Hedera helix. Each plant is described in terms of its distribution and habitat, ecological threats, physical description, means of spreading,

1. Invasive Plants Presentation
 Ailanthus altissima Tree-of-heaven
 Alliaria petiolata Garlic mustard
 Ampelopsis brevipedunculata Porcelain-berry
 Celastrus orbiculata Oriental bittersweet
 Centaurea biebersteinii Spotted knapweed
 Lespedeza cuneata Chinese lespedeza
 Lythrum salicaria Purple loosestrife
 Lonicera japonica Japanese honeysuckle
 Pueraria montana Kudzu vine
 Rubus phoenicolasius Wineberry
 Rosa multiflora Multiflora rose
 Polygonum perfoliatum Mile-a-minute
 Myriophyllum aquaticum Parrot feather
 Hedera helix English Ivy

2. Ailanthus altissima, Tree-of-heaven
Appears as single trees in the residential subdivisions
and watershed landscape.
Description from
http://dendro.cnre.vt.edu/dendrology/syllabus/factshe
et.cfm?ID=34
Leaf: Alternate, pinnately compound, 1 to 3 feet long,
with 11 to 41 leaflets, leaflets are 2 to 6 inches long,
pointed at the tip with large, glandular teeth near the
base, green above and below.
Flower: Species is deciduous; small yellow-green, in
long (6 to 12 inches) clusters, males have a
disagreeable odor, appearing in late spring to early
summer.
Fruit: An oblong, twisted samara, 1 to 1 1/2 inches
long with the seed in the center, hanging in long
clusters, ripens in late summer and disperse through
the winter.
Twig: Stout, yellow to red-brown, with fine velvety
hairs when young, easily broken with a large reddish
brown pith; buds are relatively small and half-
spherical sitting above large, heart-shaped leaf scars;
terminal bud is absent. Strong odor (some are
reminded of peanut butter) when broken.
Bark: Thin, light brown to gray, resembles the skin of
a cantaloupe when young, later turning darker gray
and rough.
Form: A short to medium sized tree to 70 feet with
heavy, open branches. Lower branches on larger
trees tend to droop. Often grows in clumps

3. Alliaria petiolate, Garlic mustard
Distribution: Found in moist to dry habitats, flood
plains and along roads. Tolerant to acid soils
and assisted to spread when white tailed deer
eat the native wildflowers.
Ecological Threat: Displaces native spring
wildflowers and the garlic chemical poisons
larvae of native butterflies and fungi associated
with native trees
Plant: biennial herb in the mustard family
(Brassicaceae); dried fruiting stalks may persist
for many months.
Leaves: crushed leaves and stems smell like
garlic; first-year leaves are kidney-shaped,
second year plants are heart-shaped with
toothed margins and pointed tips.
Spreads: a single plant can produce hundreds of
seeds, most of which fall nearby but may be
carried further by wind, water, wildlife and
people.
Look-alikes: toothworts (Cardamine or Dentaria),
sweet cicely (Osmorhiza claytonii), wild anise
(Osmorhiza longistylis) and early saxifrage
(Saxifraga virginiensis)
Description from
http://www.nps.gov/plants/alien/pubs/midatlantic/
alpe.htm

4. Ampelopsis brevipedunculata, Porcelain-berry
Distribution: Has spread in landscape from Massachusetts to
Virginia. Grows in moist soils especially along forest edges,
pond margins, stream banks in full to partial sunlight. Less
tolerant to heavy shade and permanent wetness. Survives well
after natural disturbances
Ecological Threat: Vigorous growth in open and wooded
spaces and shades out native plants. Climbs and blankets
native plants killing them.
Plant: deciduous, woody, perennial vine that resembles grape
and climbs by non-adhesive tendrils at the base of each leaf;
grows to 15-20 ft.
Leaves: alternate, simple, 3-5 lobed to highly dissected with
heart-shaped base and coarsely toothed margins, shiny
underneath with hairs on veins.
Flowers, fruits and seeds: tiny, greenish-white flowers with
petals separate at their tips occur in flat-topped clusters
opposite the leaves; appear in summer (June through August);
fruit is a speckled berry in colors ranging from aqua to pink to
purple; each berry carries 2-4 seeds.
Spreads: by seed that is eaten by birds and other small
animals and dispersed in their droppings.
Look-alikes: native species of grape (Vitis) and peppervine
(Ampelopsis) including heartleaf peppervine (Ampelopsis
cordata) which is native to the Southeast and has unlobed
leaves and smooth (hairless) stems; other
native Ampelopsis have compound leaves
Description from
http://www.nps.gov/plants/alien/pubs/midatlantic/alpe.htm

5. Celastrus orbiculata, Oriental bittersweet
Distribution: Slowly spread to 33 states. By 2011,
it was widespread in the Northeast and sporadic
but locally dominant can now be found farther
south.
Habitat: Abudant in mesic, mixed hardwood
forests and forest edges. Closely associated with
yellow poplar and less in pine, oak and maple
forests. More abundant at the headwaters of the
watershed.
Ecological Threat: Vigorous growth in wooded
spaces and uses woody shrubs and/or trees for
structural support, intertwining its branches around
support trunks and branches. Branches may
eventually overtop or shade out native plants killing
them.
 Plant: deciduous, woody, perennial vine that
can climb and/or sprawls up to 66 ft.
 Leaves: leaves are alternate, oblong, 2 to 5
inches (4-12 cm) long.
 Flowers, fruits and seeds: A typical plant
bears upwards of 370 fruits/year
 Spreads: Oriental bittersweet sprouts from
roots, root fragments, and the root crown.
Description from
http://www.fs.fed.us/database/feis/plants/vine/celor
b/all.html#Introductory

6. Centaurea biebersteinii, Spotted knapweed
Distribution: Found in every state in the U.S.
except Alaska, Georgia, Mississippi, Oklahoma,
and Texas.. Abundant in the watershed landscape
especially where precipitation ranges from 8-80
inches annualy. Survives in well-drained soils,
open pine, fir and maple forests and rangelands.
Develops deep roota that can reach water in water-
stress periods.
Ecological Threat: Dominates natural and semi-
natural habitats including barrens, fields, forests,
prairies, meadows, pastures, and rangelands.
Outcompetes native plant species, reduces native
plant and animal biodiversity, and decreases
forage production for livestock and wildlife;
degrades soil and water resources by increasing
erosion, surface runoff, and stream sedimentation.
It has increased at an estimated rate of 27% per
year since 1920.
 Plant: Can live 3-7 years with reproduction by
seed. Seeds remain viable for 5-8 years after
dispersal normally by animals and humans
activities.
 Flowers: Purple to pink, 25-35 per head;
blooms june to October. Heads are oblong or
oval and found lone or in clusters
 Spreads: Seeds dispersed and faster
sprouting after natural disturbances.
Description from
http://www.nps.gov/plants/alien/fact/cest1.htm

7. Lespedeza cuneate, Chinese lespedeza
Distribution and Habitat: Found in landscapes of the eastern
U.S.; in fields, floodplains, pond borders, stream banks, swamps,
meadows, open woodlands, roadsides and other disturbed
grounds. Found in sunny habitat and less in shaded areas such
as forest with thick canopies.
Ecological Threat: An invasive plant that threaten native species
in open areas of the meadows, prairies, open woodlands, wetland
borders and fields. Grows rapidly and displaces native plants,
forming extensive monocultures with extensive seed bank in the
soil. The seeds have long residence while the plant itself is not
good as forage for livestock and wildlife.
 Plant: warm season, perennial herbaceous plant with an erect
growth form, 3-5½ feet in height; mature stems are somewhat
woody and fibrous with sharp, stiff, flattened bristles.
 Leaves: each leaf is divided into three smaller leaflets which are
narrowly oblong and pointed, with awl-shaped spines and wedge-
shaped bases; leaflets are covered with densely flattened hairs,
giving a grayish-green or silvery appearance.
 Flowers, fruits and seeds: flowers small (about ¼ in.) creamy
white to pale yellow with central purple spots, single or in clusters
of 2-4 in axils of upper and median leaves, summer; fruits form in
fall; seeds tiny, bean-shaped, yellow to light brown.
 Spreads: by seed that is consumed by animals such as bobwhite
quail and passed through digestive tract and deposited in new
locations.
 Look-alikes: other species of Lespedeza including native and non-
native species.
 Description from http://www.nps.gov/plants/alien/fact/cest1.htm

8. Lythrum salicaria, Purple loosestrife
Distribution and Habitat: Found in every state except Florida. This
plant species has invaded wetlands, wet freshwater meadows,
tidal and non-tidal marshes, river and stream banks, pond edges,
reservoirs and ditches. In the Rapid River watershed mostly along
road divides, plant plots and lawns.
Ecological Threat: Grows fast and establishes itself replacing
native vegetation with a dense, homogeneous stand that reduces
local biodiversity, endangers rare species and provides little value
to wildlife.
 Plant: erect perennial herb with a square, woody stem
usually covered by downy hair; 4-10 ft. high, depending upon
conditions.
 Leaves: lance-shaped, stalk-less and rounded to heart-
shaped at the base; arranged in pairs or whorls around the
stem.
 Flowers, fruits and seeds: Has magenta-colored flower
spikes throughout much of the summer. Individual flowers
have five to seven petals. A single mature plant can have 30-
50 stems arising from one rootstock, and can produce an
estimated two to three million seeds per year. The flowering
season can go from June to September; flowers pollination
by insects attracted to it by abundant supply of nectar.
 Spreads: Produces vast quantities of seeds, dispersed by
wind and water. Readily reproduces vegetatively through
underground stems at a rate of about one foot per year.
 Look-alikes: from a distance, purple loosestrife may be
confused with blue vervain (Verbena hastata), blazing star
(Liatris aspera and L. spicata), Canada germander (Teucrium
canadense), swamp milkweed (Asclepias incarnata), and
fireweed (Chamaenerion angustifolium).
 Description from
http://www.nps.gov/plants/alien/pubs/midatlantic/lysa.htm

9. Lonicera japonica, Japanese honeysuckle
Distribution and habitat: Introduced from Japan in the 1800’s
as an ornamental plant, for erosion control, and for wildlife
forage and cover. Its highly fragrant flowers provide a tiny
drop of honey-flavored nectar enjoyed by children. Found in
many regions that do not have severe winter temperatures.
Inhabits fields, forests, wetlands, barrens, and disturbed
lands.
Ecological Threat: This invasive has as few natural enemies
allowing it to spread widely and out-compete native plant
species. Its evergreen to semi-evergreen hence has added
growth advantage over winter stresses native species. Kills
especially shrubs and young trees by girdling when vines
twist tightly around stems and trunks, cutting off the flow of
water through the plant. Also covers the vegetation cutting-
off sunlight from reaching native plant species and spreads
quickly through rapid rooting in the soils.
 Growth and spread: Through vegetative (plant growth)
and sexual (seed) means. Produces long vegetative
runners that develop roots where stem and leaf
junctions (nodes) come in contact with moist soil.
Underground stems (rhizomes) help to establish and
spread the plant locally. Long distance dispersal is by
birds and other wildlife
Description from
http://www.nps.gov/plants/alien/fact/loja1.htm

10. Pueraria montana, Kudzu vine
Distribution and Habitat: Predominantly found in the
eastern U.S., but spreading to other landscapes. In the
Rapidan River watershed found along the riparian areas.
Grows in wide range of conditions and soil types with
habitats preferred habitats being open, sunny areas like
forest edges, abandoned fields, roadsides and disturbed
areas. Grows best in mild winter regions with about 40
inches precipitation.
Ecological Threat: Rapid and expansive growth (much as
1 foot a day) covering the native plant species denying
then sunlight. Kill trees through girdling and the extra
weight of vines can lead to toppling during storms.
 Plant: climbing perennial vine in the pea family
(Fabaceae)Leaves: alternate, deciduous, and
compound, with three broad leaflets up to 4 in.
across, leaflets may be entire or lobed with hairy
margins.
 Spreads: By vegetative means through runners &
rhizomes and by vines that root at the nodes and
also through see where resin bee serves as a
pollinator.
 Look-alikes: Thick tangles of various vines
including grape, porcelainberry and bittersweet may
be mistaken for kudzu as well as some native
three-leaved vines in the pea family.
Description from
http://www.nps.gov/plants/alien/pubs/midatlantic/pumol.ht
m

11. Rubus phoenicolasius, Wineberry
Distribution and Habitat: Found in the region from New
England to North Carolina. Occurs along forest, field,
stream and wetland edges and in open woods, preferring
moist habitats. Has noticeable presence in patch areas of
forested Rapidan River headwaters.
Ecological Threat: Forms dense cover and shady thickets
that displacing native plants and altering habitat structure.
 Plant: multi-stemmed shrub with spiny stems
densely covered with reddish, glandular hairs, also
on flowering stems and buds.
 Leaves: alternate, divided into three leaflets with
toothed margins, terminal leaflet largest; undersides
conspicuously white.
 Flowers, fruits and seeds: flowers with five white
petals occur in springtime; bright red edible berries
produced in early summer.
 Spreads: Seed is consumed and dispersed by
birds and mammals &humans and by vegetative
means when new plants grow from the tips of
canes that touch the ground and new plants sprout
from root buds.
Description from:
http://www.nps.gov/plants/alien/pubs/midatlantic/ruph.htm

12. Rosa multiflora, Multiflora rose
Distribution and Habitat: Found in most of the eastern,
Washington and Oregon. Can withstand wide range of soil,
moisture and light conditions and is able to invade fields,
forests, prairies, some wetlands and many other habitats.
Ecological Threat: Grows aggressively and produces large
numbers of fruits (hips) that are eaten and dispersed by a
variety of birds. Dense thickets cover native shrubs and herbs
from establishing and may be detrimental to nesting of native
birds.
 Plant: multi-stemmed shrub, sometimes climbing vine,
with arching stems and recurved thorns.
 Leaves: divided into five to eleven sharply toothed
leaflets; leaf stalks with fringed stipules (paired wing-like
structures).
 Flowers, fruits and seeds: clusters of showy, fragrant,
white to pinkish, 1 in. wide flowers appear during May;
small bright red fruits, or rose hips, develop during the
summer and remain on the plant through the winter.
 Spreads: Reproduces by seed and by forming new
plants from the tips of arching canes that can root where
they contact the ground. An average plant produces an
estimated one million seeds per year, which remain
viable in the soil for up to 20 years.
 Look-alikes: Rasture rose (Rosa carolina); swamp rose
(Rosa palustris); Allegheny blackberry (Rubus
allegheniensis); flowering raspberry (Rubus odoratus).
Only multiflora rose has the combination of upright
arching stems and fringed stipules.
Description from:
http://www.nps.gov/plants/alien/pubs/midatlantic/romu.htm

13. Polygonum perfoliatum, Mile-a-minute
Distribution and Habitat: Found in parts of Connecticut,
Delaware, Massachusetts, Maryland, New Jersey, New
York, Ohio, Pennsylvania, Rhode Island, Virginia, West
Virginia, and Washington, DC. Establishes on stream
banks, parks, open space, road shoulders, forest edges
and fence lines.
Ecological Threat: Grows rapidly, covering shrubs and
other vegetation, blockings sunlight and overwhelm them
with the excessive weight causing distortion of stem and
branches. Due to expansive nature, a threat to forest
operations, nurseries and horticultural crops. Stems are
armed with recurved barbs which are also present on the
underside of the leaf blades
 Leaves: Leaves are shaped like an equilateral
(equal-sided) triangle and alternate along the
narrow, delicate stems. Distinctive circular, cup-
shaped leafy structures, called ocreae, surround
the stem at nodes, thus the name ‘perfoliata.
 Flowers, fruits and seeds: Flower buds, and later
flowers and fruits, emerge from within the ocreae.
The fruits are attractive, deep blue and arranged in
clusters at terminals. Each berry-like fruit contains a
single glossy, black or reddish-black hard seed
called an achene
 Spreads: primarily a self-pollinating plant. Vines
generally die with the first frost.
Description from:
http://www.nps.gov/plants/alien/fact/pepe1.htm

14. Myriophyllum aquaticum, Parrot feather
Distribution and Habitat: Found in at least 26 states throughout the
United States. It is limited to non-tidal, freshwater, slow-moving water
bodies including tributaries, ponds, lakes and canals. It prefers good
light, slightly alkaline and high-nutrient environments. Mostly in ponds,
lakes and small streams in Rapidan River watershed.
Ecological Threat: Forms dense mats and compete with native aquatic
plants, especially in shallow ponds. It also provides habitat for
mosquito larvae, impedes boats and clogs drainage ditches.
 Plant: aquatic plant with stout elongate stems suspended in the
water column and/or floating; both stems and submerged leaves
may be reddish tinted; gray-green tips of the stems with leaves
may protrude above the water.
 Leaves: well-developed, finely pinnately divided, in whorls of
mostly five with smooth leaf margins.
 Flowers, fruits and seeds: flowers and fruits, if present emerge
from axils of leaves.
 Spreads: vegetatively from whole plants or fragments; it can be
dispersed by people dumping aquaria into rivers and ponds and
by animals carrying fruits and fragments on their bodies.
 Look-alikes: many species of submerged aquatic plants
including non-native invasive Eurasian water-milfoil
(Myriophyllum spicatum), and native species such as Northern
water-milfoil (M. sibiricum), coontail (Ceratophyllum dmersum)
and water marigold (Megalodonta beckii).

 Description from:
http://www.nps.gov/plants/alien/pubs/midatlantic/myaq.htm


15. Hedera helix, English Ivy
Distribution and Habitat: Common in lawns and landscape in the
eastern U.S. Used in many residential subdivisions in the
Rapidan River watershed as ground cover. Establishes under
shady to full sun conditions in soils that are moderately fertile.
Habitats invaded include forest openings and edges, fields, cliffs,
steep slopes, and disturbed areas.
Ecological Threat; Aggressive invader on the ground and on
trees, blocks sunlight and weighs heavy on vascular plants killing
them. Is reservoir for bacterial leaf scorch (Xylella fastidiosa), a
harmful plant pathogen that affects a wide variety of native and
ornamental trees such as elms, oaks and maples.
• Plant: evergreen perennial climbing vine that attaches to
bark of trees, brickwork and other surfaces by root-like
structures that exude a glue-like substance to aid in
adherence.
• Leaves: alternate, dark green, waxy, somewhat leathery;
extremely variable leaf forms, from unlobed to 3-5 lobed;
typically green with whitish veins.
• Flowers, fruits and seeds: flowering occurs in late summer
to early fall, typically under full sun conditions; flowers are
small, greenish-yellow and occur in globular starburst type
inflorescences at tips of flowering stems; fruits are black
with a fleshy outer layer and stone-like seeds.
• .
 Description from:
http://www.nps.gov/plants/alien/pubs/midatlantic/hehe.htm