Section 3C.
Information on selected invasive species of the Eastern Region

Latest revision of this information: 3/30/98 by Ian Shackleford

Acer platanoides L.

Family: Aceraceae

Common Name: Norway maple

Form: tree; resembles sugar maple.

Listed: Reported as invasive in Maine, Maryland, Massachusetts, New York, Ohio, Pennsylvania, and Vermont.

Distribution: Iowa and Missouri.

Habitat: A widely planted tree, often found as an escape from cultivation in vacant lots, and now spreading into successional forests (Gleason and Cronquist, 1991)

Native Range: Europe

References: (Webb, 1996)

Aegopodium podagraria L.

Family: Apiaceae

Common Name: Goutweed

Form: perennial herb with biternately compound leaves , sharply serrate leaflets, and flowers in umbels

Listed: Reported as invasive in Connecticut, Massachusetts, and Vermont.

Distribution: Reported from every state in our region except Iowa.

Habitat: "Cultivated in old-fashioned gardens and often escaped in the north-eastern United States, especially in moist, partly shaded places."

(Gleason and Cronquist, 1991).

Native Range: Eurasia

References: No references with control information known.

Ailanthus altissima (Mill.) Swingle

Family: Simaroubaceae

Common Name: Tree-of-heaven

Form: tree with large pinnately compound leaves (each leaf with 11-41 leaflets), small green flowers in large terminal pyramidal panicles, and samaras with distinct seeds in the center

Listed: Reported as invasive in Connecticut, Missouri, New York, Ohio, Pennsylvania, and Vermont.

Distribution: Reported from every state in our region except Minnesota, New Hampshire, and Vermont.

Habitat: "...especially in alleys, beside walls and buildings, and in similar narrow places; also in fields, meadows, dumpsites; on shores and river banks; and along railroads." (Voss, 1985)

Native Range: east Asia

References: Hoshovsky (1995)

Alliaria petiolata (Bieb.) Cavara & Grande

= Alliaria officinalis Andrz.

Family: Brassicaceae

Common Name: Garlic Mustard

Form: Biennial herb with coarsely toothed triangular to spade-shaded leaves and white flowers.

Listed: Reported as invasive in Connecticut, Indiana, Iowa, Maryland, Massachusetts, Missouri, New York, Ohio, Pennsylvania, Vermont, and Wisconsin.

Distribution: Reported from every state in our region except Rhode Island.

Habitat: gardens, roadsides, and moist woods

Native Range: Europe

References: Hoffman and Kearns (1997), Carroll and White (1997), Nuzzo (1991)

Ampelopsis brevipedunculata (Maxim.) Trautv.

Family: Vitaceae

Common Name: Porcelain-berry

Form: Vine with 3-lobed leaves and blue, marbled, and white hard berries.

Listed: Reported as invasive in Connecticut, Massachusetts, Pennsylvania, and New York.

Distribution: Reported in Connecticut, Delaware, Illinois, Maryland, Massachusetts, Michigan, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, and Rhode Island.

Habitat:

Native Range: north-east Asia

References: Antenen (1996), Virginia Native Plant Society (1998)

Berberis thunbergii DC

Family: Berberidaceae

Common Name: Japanese barberry

Form: Shrub with spines, simple leaves, and red berries,

Listed: Reported as invasive in Connecticut, Maine, Massachusetts, New York, Pennsylvania, and Vermont.

Distribution: Reported from every state in our region.

Habitat: "Widely cultivated, especially for hedges, and occasionally escaping into woods, swamps, fields, and dunes." (Voss, 1985).

Native Range: Japan

References: Hoffman and Kearns (1997)

Berberis vulgaris L.

Family: Berberidaceae

Common Name: Common barberry

Form: Shrub with spines, simple leaves with spinulose margins, and red berries,

Listed: Reported as invasive in Connecticut, Massachusetts, New York, Ohio, Pennsylvania, and Vermont.

Distribution: Reported from every state in our region except Minnesota.

Habitat: "Woods, thickets, meadows, river banks." (Voss, 1985)

Native Range: Europe

References: No references with control recommendations have been found for this species. Control methods are likely similar to those for Berberis thunbergii.

"The alternate host of the common "stem" rust of wheat." (Gleason and Cronquist, 1991)

Bromus inermis Leysser.

Family: Poaceae

Common Name: Smooth brome

Form: Perennial grass with rhizomes.

Listed: Reported as invasive in Illinois, Indiana, Ohio, and Wisconsin.

Distribution: Reported from every state in our region.

Habitat: "Roadsides, fields, and waste ground, sometimes spreading to woods, shores, and other habitats; the rhizomes make this an excellent grass to hold the soil of roadside banks." (Voss, 1972) "Smooth brome invades open natural communities, such as prairies and savannas. It

appears to prefer mesic and dry-mesic situations and rarely occurs in open, wet natural areas such as sedge meadows and wet prairies. This highly persistent grass forms a dense sod that can exclude other species and lower biodiversity of native plants. It spreads to and within natural areas both by seed and vegetative means." (Solecki, 1992)

Native Range: Europe

References: Solecki (1992)

Butomus umbellatus L.

Family: Butomaceae

Common Name: Flowering rush

Form: Perennial emergent aquatic herb with rhizomes, linear leaves, and showy pink in an umbel.

Listed: Reported as invasive in New York and Vermont. A prohibited exotic aquatic weed in New Hampshire.

Distribution: "Thoroughly established on shores and riverbanks in the St. Lawrence River valley and in Lake Champlain, and more recently spread inland" (Gleason and Cronquist, 1991). Reported in Connecticut, Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, Vermont, and Wisconsin.

Habitat: aquatic along shores and riverbanks

Native Range: Eurasia

References: Haber (1997)

Celastrus orbiculatus Thunb.

= Celastrus orbiculata Thunb.

Family: Celastraceae

Common Name: Asiatic Bittersweet, Oriental bittersweet, Round-leaved bittersweet

Form: woody vine with simple leaves, small green flowers, and green to orange fruits.

Listed: Reported as invasive in Connecticut, Illinois, Indiana, Maine, Massachusetts, Missouri, New York, Ohio, Pennsylvania, and Wisconsin.

Distribution: Reported from every state in our region except Minnesota, Missouri, and Wisconsin.

Habitat: "Round-leaved bittersweet mainly is associated with old home-sites where it has escaped from cultivation into surrounding natural communities. It occurs in a variety of forest types, including undisturbed mesic and dry-mesic forest. It also is found in disturbed open areas such as

roadsides." (Hutchinson, 1990)

Native Range: east Asia

References: Hutchinson (1990)

Centaurea maculosa Lam.

Family: Asteraceae

Common Name: Spotted Knapweed, Bachelors buttons

Form: herb with pinnatifid leaves and pink-purple flowers in discoid heads

Listed: Reported as invasive in Connecticut, Indiana, Massachusetts, New York, and Wisconsin.

Distribution: Reported from every state in our region.

Habitat: old fields, roadsides, disturbed ground, and waste places (Voss, 1996).

Native Range: Europe

References: Carroll and White (1997), Hoffman and Kearns (1997)

Cirsium arvense (L.) Scop.

Family: Asteraceae

Common Name: Canada-thistle

Form: Robust perennial with deep creeping roots and red-flowered discoid heads.

Listed: Reported as invasive in Delaware, Illinois, Indiana, Missouri, Minnesota, Ohio, and Wisconsin. Steve Young, in his invasive plant list for New York (1996), considers Cirsium arvense to be an "aggressive invasive primarily on agricultural land." Cirsium arvense is a

state-listed noxious weed in Delaware, Illinois, Indiana, Iowa, Maryland, Michigan, Minnesota, Missouri, Ohio, Pennsylvania, and Wisconsin.

Distribution: Widely introduced in northern U.S. and southern Canada. Reported from every state in our range.

Habitat: fields and waste places

Native Range: Eurasia

References: Lorenzi & Jeffery (1987), Sather (1987a), Hoffman and Kearns (1997), Carroll and White (1997)

Cirsium palustre (L.) Scop.

Family: Asteraceae

Common Name: European Swamp Thistle, Marsh thistle,

Form: Perennial herb with deep creeping roots, spiny-winged stem, pinnatifid-toothed leaves, and purple flowers in discoid heads.

Listed: On the Connecticut species list, Cirsium palustre is said to be "known to be invasive in similar habitats in other states." I have observed this species invading swamp habitats in Michigan and Wisconsin.

Distribution: Reported from Massachusetts, Michigan, New Hampshire, New York, and Wisconsin.

Habitat: "Often invading woods and seemingly native." (Gleason and Cronquist, 1991). "Tall plants form dense ungainly colonies for miles along roadside ditches and adjacent swamps, where it spreads to shores and remoter wetlands. In cedar swamps and somewhat shaded fens it may try to masquerade as the native swamp thistle, C. muticum... The tragic spread of this pest into natural wetlands is doubtless aided by logging roads and other human (or inhuman) disturbance." (Voss, 1996).

Native Range: Eurasia

References: No references with control recommendations have been found for this species.

Coronilla varia L.

Family: Fabaceae

Common Name: Crown vetch

Form: perennial herb with pinnate leaves and pink flowers in long-peduncled axillary umbels

Listed: Reported as invasive in Illinois, Indiana, Maine, New York, Ohio, and Wisconsin.

Distribution: Reported from every state in our region.

Habitat: "Widely planted along highways in our range, and frequently established elsewhere." (Gleason and Cronquist, 1991). "Heavily promoted for erosion control and a rapid groundcover, becoming too well established sometimes and spreading extensively on roadsides, fields, and banks." (Voss, 1985).

Native Range: Europe

References: Carroll and White (1997), Heim (1990)

Egeria densa Planchon

Family: Hydrocharitaceae

Common Name: Brazilian water-weed

Form: Aquatic perennial herb with sparsely branched stems, cauline simple leaves, and showy flowers.

state-Listed: Reported as invasive in Connecticut, Massachusetts, and Vermont. The species is a prohibited exotic aquatic weed in New Hampshire.

Distribution: Commonly cultivated in aquaria and occasionally established in ponds in our range. Reported in Connecticut, Delaware, Illinois, Maryland, Massachusetts, New Hampshire, New Jersey, New York, Pennsylvania, and Vermont.

Habitat: ponds

Native Range: South-east Brazil to northern Argentina

References: Lorenzi and Jeffrey (1987)

Elaeagnus angustifolia L.

Family: Elaeagnaceae

Common Name: Russian olive

Form: small, thorny tree, with silvery twigs, simple lanceolate leaves, and

yellow drupe-like fruits.

Listed: Reported as invasive in Indiana, Massachusetts, New York, Ohio,

Pennsylvania, and Vermont.

Distribution: Reported from every state in our region except Delaware,

Indiana, New Hampshire, and West Virginia,

Habitat: "Escaping to fields, river banks, and other sites." (Voss, 1985)

Native Range: east Asia

References: Muzika and Swearingen (1998)

Elaeagnus umbellata Thunb.

Family: Elaeagnaceae

Common Name: autumn olive

Form: Shrubby tree with simple leaves and red fruits.

Listed: Reported as invasive in Connecticut, Illinois, Indiana, Maine, Massachusetts, Missouri, New York, Ohio, Pennsylvania, Vermont, and Wisconsin. This species is listed as a noxious weed in twenty-three counties in West Virginia (and considered to be a state noxious weed).

Distribution: Becoming common in much of our range. Reported from every state in our range except Delaware, Indiana, Minnesota, and Wisconsin.

Habitat: "Planted for ornament or wildlife habitat and too freely escaping to roadside, woods, fields, filled land, gravel pits, and almost anywhere." (Voss, 1985)

Native Range: east Asia

References: Eckardt (1987), Carroll and White (1997), Szafoni (1990)

Epilobium hirsutum L.

Family: Onagraceae

Common Name: Hairy willow-herb

Form: Perennial herb with rhizomes, villous stems, opposite lanceolate leaves, and red flowers.

Listed: Reported as invasive in Massachusetts and New York.

Distribution: Largely restricted to our region boundaries. Reported from every state in our region except Delaware, Iowa, Minnesota, and Missouri. Outside our region, reported only from Washington.

Habitat: "Introduced in moist or wet soil, especially in disturbed sites." (Gleason and Cronquist, 1991)

Native Range: Eurasia

References:

Euonymus alatus (Thunb.) Sieb.

Family: Celastraceae

Common Name: Winged Euonymus, Winged burning-bush

Form: Shrub with twigs bearing conspicuous corky wings, opposite simple leaves, small green flowers, and purple fruits with an orange aril.

Listed: Reported as invasive in Connecticut, Indiana, Massachusetts, New York, Ohio, and Pennsylvania.

Distribution: Reported from every state in our region except Delaware, Maine, Minnesota, and Missouri.

Habitat: Widely cultivated, locally escaped, invading woodlands.

Native Range: east Asia

References: Ebinger (1996)

Euonymus fortunei (Turcz.) Hand.-Mazz.

Family: Celastraceae

Common Name: wintercreeper, Climbing Euonymus

Form: Evergreen vine with aerial rootlets, leathery opposite elliptic leaves that are veiny beneath, branches with abundant minute warts, small green flowers, and fruits pink with an orange aril. The plant forms a dense ground cover or may climb or scramble to 20 feet high.

Listed: Reported as invasive in Illinois, Indiana, Missouri, Ohio, and Pennsylvania.

Distribution: Reported from Illinois, Indiana, Massachusetts, Michigan, Missouri, New Jersey, New York, Ohio, Pennsylvania, and Rhode Island.

Habitat: "This species occurs as a cultivated plant at home sites. It has spread into several types of forest, including floodplain, mesic, and dry-mesic forest. It invades natural openings and relatively undisturbed forests." (Hutchison, 1990)

Native Range: central and west China (Mabberly, 1993).

References: Hutchison (1990)

Euphorbia esula L.

Family: Euphorbiaceae

Common Name: Leafy Spurge, Wolf's milk

Form: Perennial herb, strong-rooted, with green-yellow flowers.

Listed: Reported as invasive in Illinois, Indiana, Iowa, New York, Ohio, and Wisconsin. This is a state-listed noxious weed in Iowa, Minnesota, and Wisconsin.

Distribution: Widely established in North America from New England to the Pacific, south to Maryland, Indiana, Iowa, and Colorado. Reported from every state in our range except Rhode Island.

Habitat: "Roadsides, railroads, fields, gravel pits, and such places." (Voss, 1985)

Native Range: Eurasia

References: Hoffman and Kearns (1997), Carroll and White (1997), Cole (1990), Heidel (1982)

Festuca elatior L.

= Festuca arundinacea Schreber

Family: Poaceae

Common Name: Tall-fescue, alta-fescue

Form: Tufted perennial grass

Listed: Reported as invasive in Indiana, Missouri, Ohio, Pennsylvania, and Wisconsin.

Distribution: Every state in our range.

Habitat: "Widely planted in our range and elsewhere in the U.S. and readily escaping." (Gleason and Cronquist, 1991). "Tall fescue has been used for erosion control, as a pasture grass and, recently, a drought-resistant turfgrass. It is adapted to a variety of habitats, soils and climate ...

Tall fescue has replaced diverse native herbaceous communities, especially in remnant prairies of the Midwest and northern Texas." (Eidson, 1996)

Native Range: Europe

References: Eidson (1996)

Festuca pratensis Hudson

Family: Poaceae

Common Name: Meadow-fescue

Form: Tufted perennial grass

Listed: Reported as invasive in Illinois, Indiana, and Ohio.

Distribution: Every state in our range.

Habitat: "Roadsides, shores, meadows, and waste ground, often damp." (Voss, 1972). "Cultivated for forage and established in fields, meadows, and moist soil throughout most of the U.S. and adjacent Canada." (Gleason and Cronquist, 1991). "Fescue occasionally invades open natural communities, such as prairies and glades. In a few places, it is changing the species composition and possibly is crowding out native species. This alien species has the potential to become a significant problem because of its adaptability to poor sites, allelopathic character, and difficulty of eradication." Hutchison (1990)

Native Range: Europe

References: Hutchison (1990)

Hesperis matronalis L.

Family: Brassicaceae

Common Name: Dame's rocket

Form: Biennial or perennial herb with pubescent simple denticulate leaves and large pink flowers on a tall flowering stalk.

Listed: Reported as invasive in Connecticut, Indiana, Massachusetts, Pennsylvania, and Wisconsin.

Distribution: Reported from every state in our region.

Habitat: "An old-fashioned ornamental, escaped along roads and in open woods and moist bottomlands." (Gleason and Cronquist, 1991).

Native Range: Europe

References: Hoffman and Kearns (1997)

Hydrilla verticillata (L. f.) Royle

Family: Hydrocharitaceae

Common Name: hydrilla

Form: Aquatic perennial herb with cauline simple leaves in whorls of 3-8.

Listed: Reported as invasive in Connecticut, New York and Vermont. Hydrilla verticillata is a prohibited exotic aquatic weed in New Hampshire and is on the Federal Noxious Weed List.

Distribution: In our region, the species has been reported in Delaware and Maryland; elsewhere in the United States, the species has been found in Alabama, Arizona, California, Florida, Georgia, Louisiana, North Carolina, South Carolina, Tennessee, Texas, Virginia, and Washington.

Habitat: Ditches, canals, ponds, reservoirs, lakes (Thorne, 1993). Hydrilla favors slow moving or still water, where it blocks piers and can entangle boats and ferries. It fosters an algal growth which in turn feeds mosquitoes and increases their populations.

Native Range: Eurasia

References: "Alien Species invade U.S. Ecosystems." The Nature Conservancy, Arlington, VA.

Iris pseudacorus L.

Family: Iridaceae

Common Name: Yellow Iris, water-flag, yellow-flag

Form: Perennial herb with erect leaves and bright yellow flowers.

Listed: reported as invasive in Connecticut, Massachusetts, New York and Vermont.

Distribution: Reported from every state in our region except Iowa.

Habitat: "Swamps and shallow water along streams and ponds." (Gleason and Cronquist, 1991)

Native Range: Europe

References: Washington State University Cooperative Extension (1998)

Ligustrum vulgare L.

Family: Oleaceae

Common Name: European privet, Common privet

Form: much-branched shrub with simple dark green leaves, small panicles of white flowers, and black fruits

Listed: Reported as invasive in Connecticut, Indiana, Massachusetts, New York, Ohio, and Pennsylvania.

Distribution: Reported from every state in our region except Iowa, Missouri, and Minnesota.

Habitat: "Widely cultivated...escaping to disturbed ground and forests, dry or damp." (Voss, 1996).

Native Range: Europe

References: Haragan (1996), Tennessee Exotic Pest Plant Council (1997)

Two other invasive privet species are Ligustrum sinense Lour. (Chinese Privet) and Ligustrum japonicum Thunb. (Japanese privet).

Lonicera japonica Thunb.

Family: Caprifoliaceae

Common Name: Japanese Honeysuckle

Form: vine with large white or cream flowers and black fruit

Listed: Reported as invasive in Connecticut, Illinois, Indiana, Maine, Maryland, Massachusetts, Missouri, New York, Ohio, Pennsylvania, and Vermont.

Distribution: Reported from every state in our region except Iowa, Minnesota, and Vermont.

Habitat: "Well established in woods and fields in our range." (Gleason and Cronquist, 1991)

Native Range: east Asia

References: Nyboer (1990), Evans (1984)

Lonicera maackii (Rupr.) Maxim.

Family: Caprifoliaceae

Common Name: Amur Honeysuckle

Form: shrub white flowers, red berries, and long branches and many regularly opposite leaves

Listed: Reported invasive in Connecticut, Illinois, Indiana, Maine (?), Massachusetts, Missouri, New York, Ohio, Pennsylvania, Vermont, and Wisconsin.

Distribution: Reported from Delaware, Illinois, Indiana, Maryland, Massachusetts, Michigan, Missouri, New Jersey, Ohio, Pennsylvania, West Virginia, and Wisconsin.

Habitat: "Woods (upland and swampy), thickets, banks, fencerows, often near a landscaped source." (Voss, 1996)

Native Range: Asia

References: Carroll and White (1997), Nyboer (1990)

Lonicera morrowii A. Gray

Family: Caprifoliaceae

Common Name: Fly honeysuckle, Morrow honeysuckle

Form: Shrub with white to yellow flowers and red berries.

Listed: Reported as invasive in Connecticut, Illinois, Maine, Massachusetts, Missouri, New York, Ohio, Pennsylvania, Vermont, and Wisconsin.

Distribution: Reported from every state in our region except Delaware and Indiana.

Habitat: "Along roadsides and railroads; thickets, banks, and shores; borders of woods and invading them." (Voss, 1996)

Native Range: Japan

References: Hoffman and Kearns (1997), Nyboer (1990)

Lonicera tatarica L.

Family: Caprifoliaceae

Common Name: Tartarian honeysuckle

Form: Shrub with white to yellow flowers and red berries.

Listed: Reported as invasive in Connecticut, Illinois, Indiana, Iowa, Maine, Massachusetts, New York, Ohio, Pennsylvania, Vermont, and Wisconsin.

Distribution: Reported from every state in our region except Missouri.

Habitat: "Widely cultivated and naturalized along roadsides and railroads; thickets, shores and along rivers; borders of woods and invading them; fields and waste places." (Voss, 1996).

Native Range: Eurasia

References: Hoffman and Kearns (1997), Carroll and White (1997), Nyboer (1990)

Lonicera x bella Zabel

Family: Caprifoliaceae

Common Name: Bell's honeysuckle

Form: A hybrid between L. tatarica and L. morrowii. A shrub with pink to yellow flowers and red berries.

Listed: Reported as invasive in Connecticut, Illinois, Maine, New York, and Wisconsin.

Distribution: Reported from every state in our region except Delaware, Iowa, Missouri, and West Virginia.

Habitat: Roadsides, railroads, banks, waste places, and borders of woods (Voss, 1996).

Native Range: This is a cultivated hybrid that probably also originates in our range.

References: Hoffman and Kearns (1997), Carroll and White (1997), Nyboer (1990)

Lysimachia nummularia L.

Family: Primulaceae

Common Name: Moneywort, creeping jenny

Form: Perennial creeping herb with opposite round leaves and solitary yellow flowers in the leaf axils.

Listed: Reported as invasive in Illinois, Indiana, Massachusetts, Ohio, and Pennsylvania.

Distribution: Reported from every state in our region.

Habitat: "Its large yellow axillary flowers make it an attractive plant and its creeping habitat withstands mowing, so it thrives in some lawns, cemeteries, and borders of gardens; also found in swamp forests, on stream and river banks as well as damp shores, and in ditches and meadows."

(Voss, 1996),

Native Range: Europe

References: Lorenzi and Jeffrey (1987), Kennay and Fell (1990)

Lythrum salicaria L.

Family: Lythraceae

Common Name: purple loosestrife

Form: Stout perennial herb with opposite leaves and red flowers in spikes.

Listed: Reported as invasive in Connecticut, Illinois, Indiana, Iowa, Maine, Maryland, Massachusetts, Missouri, New York, Ohio, Pennsylvania, Vermont, and Wisconsin (every state from which we have invasive plant information). Purple loosestrife is a state-listed noxious weed in Indiana, Iowa, Minnesota, New Hampshire, Ohio, Pennsylvania, and Wisconsin.

Distribution: Newfoundland and Quebec to North Dakota, south to Virginia, Missouri, and Kansas, and occasionally west to the Pacific. Reported from every state in our range.

Habitat: wet places

Native Range: Eurasia

References: Hoffman and Kearns (1997), Heidorn (1990), Carroll and White (1997)

Melilotus alba Medikus

Family: Fabaceae

Common Name: White sweet clover

Form: Tall biennial herb with taproot and white flowers.

Listed: Reported as invasive in Illinois, Indiana, Minnesota, New York, Ohio, and Wisconsin.

Distribution: "From Nova Scotia to British Columbia, south to Mexico and the West Indies." (Gleason and Cronquist, 1991). USDA PLANTS database distribution not available.

Habitat: "Widely grown as a forage plant (and also attractive to bees), thoroughly naturalized... Characteristic of recently disturbed places in dry, open, often calcareous ground, such as sand dunes, prairies, and roadsides, as well as fields, railroads, and shores." (Voss, 1985)

Native Range: Eurasia

References: Cole (1990)

Melilotus officinalis (L.) Pallas.

Family: Fabaceae

Common Name: Yellow sweet clover

Form: Tall biennial herb with taproot and yellow flowers.

Listed: Reported as invasive in Illinois, Indiana, Minnesota, New York, Ohio, and Wisconsin.

Distribution: Reported from every state in the United States.

Habitat: "Of similar status to the preceding, becoming common somewhat more recently although apparently also established by the 1880's. Roadsides, fields, railroads, disturbed areas in woods, shores, waste places generally." (Voss, 1985).

Native Range: Eurasia

References: Cole (1990)

Microstegium vimineum (Trin.) A. Camus

Family: Poaceae

Common Name: Japanese Stilt Grass, Nepalese browntop

Form: straggling annual grass

Listed: Reported as invasive in Connecticut, Indiana, Maryland, New York, and Pennsylvania.

Distribution: Reported from Connecticut, Delaware, Illinois, Indiana, Maryland, New Jersey, New York, Ohio, Pennsylvania and West Virginia.

Habitat:

Native Range: tropical Asia

References: Swearingen (1998), LaFleur (1996)

Myriophyllum spicatum L.

Family: Haloragaceae

Common Name: Eurasian water-milfoil

Form: Submerged aquatic herb with many cauline, whorled, pinnately-dissected leaves.

Listed: Reported as invasive in Connecticut, Massachusetts, New York, Pennsylvania, Vermont, and Wisconsin.

Listed: New Hampshire

Distribution: Widely introduced in North America. Reported in every state in our region except Iowa, Illinois, Maine, Rhode Island, and West Virginia.

Habitat: submerged aquatic in ponds and lakes

Native Range: Europe

References: Hoffman and Kearns (1997)

Najas minor Allioni

Family: Najadaceae

Common Name: Naiad, eutrophic water-nymph

Form: submerged dark-green aquatic herb with slender branching stems, simple, opposite, linear, serrate leaves, and small inconspicuous flowers in the leaf axils.

Listed: Reported as invasive in Massachusetts, New York, and Vermont.

Distribution: Reported from Illinois, Indiana, Massachusetts, Michigan, New York, Ohio, Pennsylvania, Vermont, and West Virginia.

Habitat: submerged aquatic ... "Naiad grows densely near the shore of ponds, lakes, and streams and forms a thick, dark mass from the bottom to the surface." (Lorenzi and Jeffrey, 1987) ... "Ponds, lakes, and slow-moving streams, often in eutrophic or alkaline waters." (Gleason and

Cronquist, 1991)

Native Range: Eurasia and Africa

References: Lorenzi and Jeffrey (1987)

Nasturtium officinale R. Br.

= Rorippa nasturtium-aquaticum (L.) Hayek.

Family: Brassicaceae

Common Name: Watercress

Form: Perennial herb with white flowers.

Listed: Reported as invasive in Connecticut, Massachusetts, Minnesota, and New York, although likely equally naturalized throughout our range.

Distribution: Reported from every state in our region and every state in the United States except North Dakota and Hawaii.

Habitat: "Stems submersed or partly floating, or prostrate on mud, freely rooting... widely established in clear quiet water." (Gleason and Cronquist, 1991) "Margins of rivers and streams; ditches; seepy places and brooks in woods and cedar swamps- especially in cold spring-fed waters; also at home in sedgy tamarack swamps." (Voss, 1985).

Native Range: Eurasia

References: none known (?Lorenzi and Jeffrey (1987)?)

Nymphoides peltata (Gmelin) Kuntze

Family: Menyanthaceae

Common Name: Yellow floating-heart

Form: Rhizomatous perennial aquatic herb with round floating leaves and emergent yellow flowers in umbels.

Listed: Reported as invasive in Massachusetts, New York, and Vermont.

Distribution: Reported from Connecticut, Illinois, Indiana, Maryland, Massachusetts, Missouri, New Hampshire, New Jersey, New York, Ohio, Pennsylvania, Rhode Island, and Vermont.

Habitat: submerged aquatic in quiet waters

Native Range: Europe

References: No references with control information have been found for this species.

Paulownia tomentosa (Thunb.) Steudel

Family: Bignoniaceae

Common Name: Empress-tree, Princess-tree

Form: Three with simple, opposite, cordate leaves, lavender flowers in upright panicles, and persistent woody capsules.

Listed: Reported as invasive in Connecticut, Indiana, Massachusetts, and Pennsylvania.

Distribution: South-eastern United States. Reported from every state in our region except Iowa, Maine, Michigan, Minnesota, New Hampshire, Vermont, and Wisconsin.

Habitat: "Initially used as an ornamental, it has escaped cultivation in the eastern half of the U.S. In warm region it can grow in almost any habitat and is often seen in vacant lots. It is of most concern in the mid-Atlantic region and Southeast." (Johnson, 1996).

Native Range: China

References: Johnson (1996)

Poa compressa L.

Family: Poaceae

Common Name: Wiregrass, Canada Bluegrass

Form: Perennial grass with rhizomes.

Listed: Reported as invasive in Connecticut, Indiana, New York, Ohio, and Pennsylvania.

Distribution: Reported form every state in our range.

Habitat: "Widespread in old fields, roadsides, waste ground, rocky or sandy woods and openings (oak, aspen, jack pine), usually in dry places but sometimes on shores and in damp woods." (Voss, 1972)

Native Range: Europe

References: Sather (1987b)

Poa pratensis L.

Family: Poaceae

Common Name: Kentucky bluegrass

Form: Perennial grass with rhizomes. The florets have distinct webbing at their base which may be seen when a floret is removed from the glumes.

Listed: Reported as invasive in Illinois, Indiana, and Ohio.

Distribution: "A complex species mostly introduced form Eurasia and a very important cultivated pasture grass; plants of northern shores, rocks, and open woods are presumably native." (Voss, 1972). Reported form every state in our range.

Habitat: "Almost ubiquitous in all but the wettest places - waste ground, woods, dunes, fields." (Voss, 1972)

Native Range: Europe

References: Solecki (1992), Sather (1987b)

Polygonum cuspidatum Sieb. & Zucc.

= Fallopia japonica (Houtt.) Ronse Decraene

Family: Polygonaceae

Common Name: Japanese knotweed, Japanese knotwood, Mexican bamboo

Form: Coarse rhizomatous perennial herb, to 2.5 meters tall, with alternate broad leaves and racemes of small green-white flowers from leaf axils.

Listed: Reported as invasive in Connecticut, Maine, Maryland, Massachusetts, Missouri, New York, Ohio, Pennsylvania, Vermont, and Wisconsin.

Distribution: Reported from every state in our region.

Habitat: "Planted as an ornamental and occasionally found as an escape at gravel pits, filled ground, roadsides, dumps, and gullies." (Voss, 1985)

Native Range: Japan

References: Lorenzi and Jeffery (1987), Seiger and Merchant (1997)

Polygonum perfoliatum L.

Family: Polygonaceae

Common Name: mile-a-minute weed

Form: Annual climbing vine with reflexed-prickly stems.

Listed: Reprted as invasive in Maryland, Pennsylvania, and New York. This is a state-listed noxious weed in Ohio and Pennsylvania.

Distribution: Established in Maryland, Pennsylvania, and West Virginia, to be expected to spread. Reported in Maryland, New Jersey, Pennsylvania, and West Virginia.

Habitat: "Common habitats of mile-a-minute weed include roadsides, railroad sidings, stream banks, forest edges, moist open thickets and other disturbed areas. It is becoming a serious problem in reforestation of clear-cut areas, tree nurseries, orchards, recreation areas, and residential areas." (Biocontrol Mile-A-Minute Home Page, 1998)

Native Range: east Asia

References: Biocontrol Mile-A-Minute Home Page (1998), Central Maryland Research and Education Center web page (1998)

Potamogeton crispus L.

Family: Potamogetonaceae

Common Name: curly pondweed

Form: Aquatic perennial herb with cauline, simple, linear leaves; no floating leaves.

Listed: Reported invasive in Connecticut, Massachusetts, New York, Pennsylvania, Vermont, and Wisconsin. This is a state-prohibited exotic aquatic weed in New Hampshire.

Distribution: Locally introduced in alkaline or high-nutrient waters nearly throughout our range. Reported in every state in our region except Maine.

Habitat: Submerged aquatic in alkaline or high-nutrient waters.

Native Range: Europe

References: Lorenzi and Jeffery (1987)

Rhamnus cathartica L.

Family: Rhamnaceae

Common Name: common buckthorn

Form: Shrub or small tree with thorns, simple leaves, and black fruits.

Listed: Reported invasive in Connecticut, Illinois, Indiana, Maine, Massachusetts, Missouri, New York, Ohio, Pennsylvania, Vermont, and Wisconsin. A state-listed noxious weed in Iowa.

Distribution: Escaped from cultivation at many places in our range. Reported from every state in our range except Delaware, Maryland, and West Virginia.

Habitat: "Forming thickets in vacant (or occupied!) lots; at borders (even interiors) of woods; along roadsides, fencerows, railroads, river banks, and clearings; occasionally in swampy sites." (Voss, 1985).

Native Range: Eurasia

References: Hoffman and Kearns (1997); Carroll and White (1997), Heidorn (1990)

Rhamnus frangula L.

= Frangula alnus Miller

Family: Rhamnaceae

Common Name: Smooth Buck-thorn

Form: Shrub with simple leaves and red to black fruits.

Listed: Reported as invasive in Connecticut, Illinois, Indiana, Massachusetts, New York, Ohio, Pennsylvania, Vermont, and Wisconsin.

Distribution: Reported from every state in our region except Delaware and Missouri. Outside our region, known only in Colorado, Kentucky, Tennessee, and Wyoming.

Habitat: "Locally aggressive and becoming a serious pest as a tall shrub in bogs, especially alkaline ones (fens), and other damp places, including tamarack and cedar swamps (particularly in disturbed areas as along new power lines and other clearings), thickets along rivers, lake shores,

ditches, fencerows, and low woods." (Voss, 1985).

Native Range: Eurasia

References: Hoffman and Kearns (1997); Carroll and White (1997), Heidorn (1990)

Rosa multiflora Thunb.

Family: Rosaceae

Common Name: multiflora-rose

Form: Woody vine with pinnate leaves, prickles, and many white or pink flowers.

Listed: Reported as invasive in Connecticut, Illinois, Indiana, Massachusetts, Missouri, Ohio, Pennsylvania, Vermont, and Wisconsin. Steve Young, in his invasive plant list for New York (1996), considers Rosa multiflora to be an "aggressive invasive primarily on agricultural land."

Rosa multiflora is a state-listed noxious weed in Indiana, Iowa, Maryland, Missouri, Ohio, Pennsylvania, West Virginia, and Wisconsin.

Distribution: Often escaped from cultivation. Reported from every state in our range.

Habitat: "Roadsides, disturbed woods and borders, fencerows and fields, thickets and untended yards; sometimes in low ground although usually in dry places." (Voss, 1985)

Native Range: east Asia

References: Lorenzi & Jeffery (1987), Nancy (1987), Hoffman and Kearns (1997), Carroll and White (1997), Szafoni (1990)

Sorghum halepense (L.) Pers.

Family: Poaceae

Common Name: Johnson-grass

Form: Rhizomatous perennial grass to 1.5 meters tall.

Listed: Reported as invasive in Delaware, Illinois, Indiana, Missouri, and Ohio. Sorghum halepense is a state-listed noxious weed in Delaware, Illinois, Indiana, Maryland, Missouri, Ohio, Pennsylvania, and West Virginia.

Distribution: Well established as a weed especially in the south part of our range, but also north to Massachusetts and Michigan. Reported from every state in our range except Maine, Minnesota, and Wisconsin.

Habitat: "This species occurs in crop fields, pastures, abandoned fields, rights-of-way, forest edges, and along streambanks. It thrives in open, disturbed rich, bottom ground, particularly in cultivated fields." (Hutchison, 1990)

Native Range: Mediterranean region

References: Lorenzi & Jeffery (1987), Hutchison (1990)

Trapa natans L.

Family: Trapaceae

Common Name: water-chestnut

Form: Emergent-aquatic annual plant. The floating leaves form a rosette.

Listed: Reported as invasive in New York, Massachusetts, and Vermont. A state-prohibited aquatic weed in New Hampshire.

Distribution: Established and becoming abundant in the Hudson, Potomac, and Mohawk rivers, and locally elsewhere in our range. Reported in Maryland, Massachusetts, New York, Pennsylvania, and Vermont.

Habitat: emergent-aquatic

Native Range: Eurasia

References: Madsen (1993)

Ulmus pumila L.

Family: Ulmaceae

Common Name: Siberian elm

Form: Shrub or small tree with leaves uncharacteristically symmetrical.

Listed: Reported as invasive in Illinois, Massachusetts, Minnesota, Ohio, and Wisconsin.

Distribution: Reported from every state in our region except Delaware and New Jersey.

Habitat: "Native of Asia but widely planted and spreading from cultivation into vacant (and not so vacant) lots, sidewalk crevices, waste ground, shores, and woods. Evidently becoming quite aggressive in recent years." (Voss, 1985)

Native Range: Asia

References: Kennay and Fell (1990), Kennay (1996)

Valeriana officinalis L.

Family: Valerianaceae

Common Name: Garden-heliotrope, Common valerian, Garden valerian

Form: Perennial herb with pinnately divided opposite leaves and pale pink flowers in a large corymbiform inflorescence.

Listed: Reported as invasive in New York, Maine, and Wisconsin.

Distribution: Reported from every state in our region except Delaware, Missouri, and Rhode Island. Outside our region, known only in Idaho, Oregon, and Washington.

Habitat: "Often cultivated for its very fragrant flowers and occasionally established as an escape to roadsides, ditches, shores, fields, and borders of woods." (Voss, 1996).

Native Range: Eurasia

References: No references with control recommendations have been found for this species.

Vinca minor L.

Family: Apocynaceae

Common Name: Greater periwinkle

Form: Low trailing woody vine with opposite leaves and large purple flowers.

Listed: Reported as invasive in Delaware, Indiana, New York, and Ohio.

Distribution: Reported from every state in our region.

Habitat: "A native of Europe, much cultivated as a ground-cover, often spreading along roadsides and into woods and thickets, sometimes abundant and long-persisting, out-competing native vegetation." (Voss, 1996).

Native Range: southern Europe

References: Young (1996)

Vincetoxicum nigrum (L.) Moench.

= Cynanchum louiseae Kartesc & Gandhi

Family: Asclepiadaceae

Common Name: Black Swallow-wort, Louis' swallowwort

Form: Climbing perennial vine with opposite simple leaves and purple-black flowers in cymes.

Listed: Reported as invasive in Connecticut, New York, and Wisconsin.

Distribution: Reported from every state in our region except Delaware, Iowa, Minnesota, Missouri, and West Virginia. Outside our region, known only in Kansas and Florida.

Habitat: "Occasionally escaped from cultivation and locally established in woods and moist, sunny places." (Gleason and Cronquist, 1991) "Locally established as an escape from cultivation, with potential for becoming a serious weed." (Voss, 1996)

Native Range: southern Europe

References: No references with control recommendations have been found for this species.

Vincetoxicum rossicum (Kleo.) Barb.

= Cynanchum rossicum (Kleo.) Borhidi

Family: Asclepiadaceae

Common Name: Dog-strangling vine, European Swallow-wort

Form: Scrambling perennial vine with opposite simple leaves and pale purple flowers in cymes.

Listed: Reported as invasive in Connecticut, New York, and Wisconsin.

Distribution: Reported only from Michigan, New York, and Pennsylvania.

Habitat: "Occasionally introduced into thickets and waste places in our range." (Gleason and Cronquist, 1991)

Native Range: Europe

References: No references with control recommendations have been found for this species.

References

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Personal Communications

Frye, Christopher. 1998. Personal communication concerning invasive plants in Maryland. Maryland Natural Heritage & Conservation Programs, Department of Natural Resources.

Rooney, Sally C. 1998. Personal communication concerning invasive plants in Maine. (srooney@acadia.net)

Pearson, John. 1998. Personal communication concerning invasive plants in Iowa. Iowa Natural Features Inventory, Department of Natural Resources.

Vinvent, Mike A. 1998. Personal communication concerning invasive plants in Ohio. Herbarium, Department of Botany, Miami University, Ohio.

Washington State University Cooperative Extension. 1998. Iris pseudacorus. http://gardening.wsu.edu/library/natv904/natv904.htm

Windus, Jennifer. 1998. Personal communication concerning invasive plants in Ohio. Ohio Division of Natural Areas & Preserves, Department of Natural Resources, Columbus, Ohio.