Download Invasive Plant Flashcards

Japanese
Barberry
(Berberis
thunbergii)
Japanese
Knotweed
(Polygonum
cuspidatum)
Photo: www.emmitsburg.net
Description: Aggressive plant that forms thickets 3-6
feet tall. Reddish stems are hollow and bamboo-like.
Leaves alternate 3-6 inches long. White flowers in
summer, often found growing along streams.
Description: Shrub with small, straight thorns on stems; forms
thick stands in forests. Small oval leaves ½ -1 ½ in. long. Leaves
green or purple with smooth margins. Small yellow flowers in
April-May. Plant turns brilliant red in fall. Bright red berries late fall
& winter.
Mile-a-Minute
(Persicaria perfoliata)
Japanese
honeysuckle
(Lonicera
japonica)
Photo: www.nps.gov
Description: Perennial woody vine. Leaves are
opposite, oval in shape. White flowers appear in
late spring through early summer, often with yellow
tinge. Small black fruits visible in fall.
Description: Herbaceous, prickly vine with light
green, alternate, triangular leaves. Round, leafy
structures surround stem at nodes. Flowers small
and white, with deep blue fruits in fall.
Photos from
www.duke.edu
Photo: www.mdinvasivesp.org
Photo: www.dkimages.com
Garlic Mustard
(Alliaria petiolata)
Description: Coarsely toothed leaves give off a
garlicky smell when crushed. Grows quickly in early
spring. Four-petaled, white flowers in spring; dies off
by late June leaving elongate seedpods. Edible.
Multiflora Rose
(Rosa multiflora)
Description: A thorny shrub with arching stems;
climbs trees and other shrubs. Leaves divided in
five to eleven sharply toothed leaflets. Fringed
stipules (tiny leaf-like structures at base of leaf
stems). White rose-like flowers appear in May.
Russian olive
(Eleagnus
angustifolia)
Description: A small, thorny shrub or small tree.
Leaves egg or lance-shaped with smooth margins,
alternating along the stem. Flower and leaves covered
with silvery scales.
Purple Loosestrife
(Lythrum salicaria)
Description: Woody
stem, 4-10 feet high.
Lance-shaped leaves,
paired in whorls around
stem. Many purple
flowers from summer
through fall. Typically
found in open meadows
and marsh areas.
Photo: www.cwss-scm.ca
Photo: www.highriver.ca
Dames Rocket
(Hespersis matronalis)
Oriental
Bittersweet
(Celastrus
orbiculata)
Description: Flowers
purple or white, visible in
May and June. Often
confused with wild phlox.
Phloxes have 5 petals;
Dames rocket has 4 petals.
Alternate leaves are lancelike and toothed. Phlox
leaves are smooth and
opposite.
Description: Woody vine; often wraps around trees.
Alternate, rounded leaves are finely toothed with small
point at tip. Small, greenish flowers found where leaf
meets the stem. Small red fruits in the fall.
Exotic Bush
Honeysuckle
(Lonicera
spp.)
Tree of
Heaven
(Ailanthus
altissima)
Photo: www.wmnu.edu
Description: Shrub. Can grow up to 20 ft tall.
Opposite leaves with oval leaflets. Flowers can be
white to pink to red or yellow, depending on species.
Stems typically hollow. Fruits red to orange.
Description: Tree. Can grow up to 80 ft tall. Each
compound leaf has 11-25 smaller leaflets. Base of
leaflet has small ‘whale tail.’ Also called stinking sumac
for strong odor. Yellowish flowers bloom mid-June.
Common Buckthorn
(Rhamnus cathartica )
Spotted Knapweed
(Centaurea maculosa)
Description: Shrub or
small tree. Broad, oval
opposite and/or alternate
leaves with jagged,
toothed margins and
arcuate veins. Twigs often
tipped with thorn. Yellowgreen flowers in spring.
Description: 2-4 ft tall
herb. Alternate, pale
green leaves 1-3 in long.
Purple, many-petaled
flowers bloom from July
through August. Prefers
dry areas. Releases a toxin
that reduces growth of
other species.
Photo: www.invasive.org
Photo: www.nps.gov
Pale Swallowwort
(Cynanchum rossowii)
Description: Non-woody
vine. Oval to lance-like,
opposite leaves. Pink to
brown, 5-petaled flowers.
Fruits a smooth, slender,
light green pod that
forms in July and August.
Photo: www.nps.gov
Norway Maple
(Acer
platanoides)
Photo: www.wikipedia.org
Description: Large, deciduous tree. Twigs and leaves
ooze milky sap when cut or torn. Leaves are wider than
they are long with what looks like 7 lobes. Turn bright
yellow in late fall. Fruit appears more linear than
native maples, which have more sharply V-shaped
fruit. Causes very thick shade beneath.
Photos: www.nps.gov and
www.swallow-wort.com
Photo: www.colby-sawyer.edu
Photo: www.sdstate.edu
Photo: www.co.stevens.wa.us
Winged
Burning
Bush
(Euonymus
alatus )
Description: Shrub often planted along roads and
in gardens, because it turns bright red in the fall.
Leaves 1-3” long, medium to dark green except in
fall. Small yellow or green flowers in May or early
June. Very obvious woody “wings” on stems.
Water
chestnut
(Trapa
natans)
Description: Aquatic floating plant found in quiet,
freshwater parts of the Hudson River. Leafs out in
mid-summer creating thick beds of vegetation.
Distinctive black seeds with spikes are found on
most shorelines in the region.
Common
reed
(Phragmites
australis)
Description: Tall grass found in marsh areas. Often
over 10-12’ tall. Sometimes described as ‘really
tall wheat’– has feathery flower heads that sway in
wind, similar to what can be seen in wheat fields.
Woody “wings”
on stem