Individual Species Account

This list, as a pamphlet, is available for distribution from:
The CT Geological and Natural History Survey
860-424-3585

Non-Native Invasive & Potentially Invasive
Vascular Plants in Connecticut

1 JAN 2000

The following list has been developed using criteria created for this purpose. Species on the list are either potentially invasive or invasive. Invasive species are either widespread or have a restricted range in Connecticut. These two terms are geographic descriptors and do not imply degree of invasiveness. The list is intended to be an educational tool. This list is not static and will be reevaluated in December 2000. A species as listed here includes all subspecies, varieties, forms and cultivars. Life forms and broad habitat descriptors for habitats that are primarily threatened are noted.

WIDESPREAD AND INVASIVE

POTENTIALLY INVASIVE

RESTRICTED AND INVASIVE

* LIFEFORM AND HABITAT

WIDESPREAD AND INVASIVE Top of Page

SCIENTIFIC NAME	COMMON NAME	LIFEFORM1	HABITAT2
Ailanthus altissima (Mill.) Swingle	Tree-of-heaven	T	U
Alliaria petiolata (Bieb.) Cavara & Grande	Garlic Mustard	H	U
Berberis thunbergii DC.	Japanese Barberry	S	U
Celastrus orbiculatus Thunb.	Asiatic Bittersweet	V	U
Centaurea maculosa Lam.	Spotted Knapweed	H	O
Elaeagnus umbellata Thunb.	Autumn Olive	S	O
Euonymus alatus (Thunb.) Sieb.	Winged Euonymus	S	U
Euphorbia cyparissias L.	Cypress Spurge	H	O
Frangula alnus Mill.	European Buckthorn	S	U
Hesperis matronalis L.	Dame's Rocket	H	U
Lonicera x bella Zabel	Bella Honeysuckle	S	U, W
Lonicera japonica Thunb.	Japanese Honeysuckle	V	U, W
Lonicera morrowii A. Gray	Morrow's Honeysuckle	S	U, W
Lythrum salicaria L.	Purple Loosestrife	H	W
Nasturtium officinale R. Br.	Watercress	H	W
Phragmites australis (Cav.) Trin.	Common Reed	G	U, W
Polygonum cuspidatum Sieb. & Zucc.	Japanese Knotweed	H	U, W
Potamogeton crispus L.	Crispy-leaved Pondweed	A	R, L
Rhamnus cathartica L.	Buckthorn	S	U
Robinia pseudoacacia L.	Black Locust	T	U
Rosa multiflora Thunb.	Multiflora Rose	S	U
Vincetoxicum nigrum (L.) Moench.	Black Swallow-wort	H,V	U
Vincetoxicum rossicum (Kleo.) Barb.	Swallow-wort	H,V	U

RESTRICTED AND INVASIVE Top of Page

SCIENTIFIC NAME	COMMON NAME	LIFEFORM1	HABITAT2
Ampelopsis brevipedunculata (Maxim.) Trautv.	Porcelain berry	V	U
Cabomba caroliniana A. Gray	Fanwort	A	L, R
Cardamine impatiens L.		H	U
Egeria densa Planchon	Brazilian Water-weed	A	L, R
Froelichia gracilis (Hook.) Moq.	Cottonweed	H	O
Humulus japonicus Sieb. & Zucc.	Japanese Hops	H,V	W, U
Hydrilla verticillata (L. f.) Royle	Hydrilla	A	L, R
Iris pseudacorus L.	Yellow Iris	H	W
Lepidium latifolium L.	Tall Pepperwort	H	C, O
Lysimachia vulgaris L.	Garden Loosestrife	H	W
Microstegium vimineum (Trin.) A. Camus	Japanese Stilt Grass	G	U
Myriophyllum heterophyllum Michx.	Variable Water-milfoil	A	L, R
Myriophyllum spicatum L.	European Water-milfoil	A	L, R
Rubus phoenicolasias Maxim.	Wineberry	S	U
Trapa natans L.	Water Chestnut	A	L, R
Tussalago farfara L.	Coltsfoot	H	U, W

POTENTIALLY INVASIVE Top of Page

SCIENTIFIC NAME	COMMON NAME	LIFEFORM1	HABITAT2
Acer ginnala L.	Amur Maple	T	U
Acer platanoides L.	Norway Maple	T	U
Acer pseudoplatanus L.	Sycamore Maple	T	U
Aegopodium podagraria L.	Goutweed	H	W
Aira caryophyllea L.	Silver Hairgrass	G	O
Allium vineale L.	Wild Garlic	H	U
Amorpha fruticosa L.	False Indigo	S	W
Arthraxon hispidus (Thunb.) Makino	G	O, W
Berberis vulgaris L.	Barberry	S	U
Bromus tectorum L.	Drooping Brome-grass	G	O
Butomus umbellatus L.	Flowering-rush	H	W
Callitriche stagnalis Scop.	A	R, W
Cirsium arvense (L.) Scop.	Canada Thistle	H	O
Datura stramonium L.	Jimson-weed	H	C
Elaeagnus angustifolia L.	Russian Olive	S	U
Elsholtzia ciliata (Thunb.) Hylander	Elsholtzia	H	U
Euphorbia esula L.	Leafy Spurge	H	O
Geranium nepalense Sweet	Nepalese Crane's-bill	H	U
Glechoma hederacea L.	Gill-over-the-ground	H	W
Kochia scoparia (L.) Schrader	Summer Cypress	H	C
Ligustrum obtusifolium Sieb. & Zucc.	Border Privet	S	U
Ligustrum ovalifolium Hassk.	California Privet	S	U
Ligustrum vulgare L.	European Privet	S	U
Lonicera maackii (Rupr.) Maxim.	Amur Honeysuckle	S	U
Lonicera tatarica L.	Tatarian Honeysuckle	S	U
Lonicera xylosteum L.	European Fly-honeysuckle	S	U
Lychnis flos-cuculi L.	Ragged Robin	H	O
Lysimachia nummularia L.	Moneywort	H	W
Marsilea quadrifolia L.	Water Shamrock	H	L
Miscanthus sinensis Anderss.	Eulalia	G	O
Myosotis scorpioides L.	Forget-me-not	H	W
Myriophyllum aquaticum (Vell.) Verdc.	Parrotfeather	A	L
Nelumbo lutea (Willd.) Pers.	American Water Lotus	A	L
Najas minor Allioni	Eutrophic Water-nymph	A	L
Ornithogalum umbellatum L.	Star of Bethlehem	H	U
Paulownia tomentosa (Thunb.) Steudel	Empress-tree	T	U, C
Phalaris arundinacea L.	Reed Canary-grass	G	W
Poa compressa L.	Canada Blue-grass	G	U
Polygonum cespitosum Blume	H	U
Polygonum perfoliatum L.	Mile-a-minute Vine	V, H	U
Populus alba L.	White Poplar	T	U
Pueraria lobata (Willd.) Owhi	Kudzu-vine	V	U
Ranunculus ficaria L.	Lesser Celandine	H	U, W
Rosa rugosa Thunb.	Japanese Rose	S	C
Rumex acetosella L.	Sheep Sorrel	H	U
Silphium perfoliatum L.	Cup-plant	H	U
Solanum dulcamara L.	Climbing Nightshade	H, V	U, W
Valeriana officinalis L.	Garden-heliotrope	H	U
Veronica beccabunga L.	Brooklime	H	W

LIFEFORMS1 AND HABITATS 2 Top of Page

LIFEFORMS 1	HABITATS 2
T = tree	U = uplands (all upland habitats including closed-canopy forests, second-growth woods, fields, grasslands, ridge tops, sand barrens, pitch pine scrublands etc.)
S = shrub	O = open areas (fields, grasslands, sand barrens, dry meadows etc.)
V = vine	W = wetlands (swamps, marshes, wet meadows, fens, bogs, flood plains, flood plain forests, pond and stream shores)
H = herbaceous plant	L = lakes (ponds, in impounded water)
G = grass	R = rivers (streams, in running water)
A = aquatic	C = coast (sand dunes, rocky headlands, upper edges of salt water tidal marshes)

List and criteria developed by the George Safford Torrey Herbarium at the University of Connecticut in conjunction with the State Geological and Natural History Survey of Connecticut and the Connecticut Invasive Plant Working Group. Here are the criteria for determining if a species is invasive in Connecticut.

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