University of Connecticut University of UC Title Fallback Connecticut

Invasive Plant List

Click below to view the Connecticut Invasive Plant List. The list includes Invasive and Potentially Invasive Plants as determined by the Connecticut Invasive Plants Council in accordance with Connecticut General Statutes §22a-381a through §22a-381d. The list was most recently revised in November 2014.

2014 Revised CT Invasive Plant List sorted by scientific name (PDF)  

(P) indicates Potentially Invasive (all others are considered Invasive in Connecticut)

“Prohibited by Statute?” column indicates prohibited status: Yes=prohibited from importation, movement, sale, purchase, transplanting, cultivation and distribution under CT General Statutes §22a-381d; N/A=not prohibited

SPECIES

(SCIENTIFIC NAME)

SPECIES(COMMON NAME) GROWTH FORM OR HABIT PROHIBITED BY STATUTE? FACTSHEETS* PHOTOS GO BOTANY LINK ID SHEETS
Acer ginnala
Amur maple (P) Tree  N/A PA DCNR; NRCS  Invasive.org  Go Botany
Acer platanoides Norway maple Tree  N/A CIPWG; PA DCNR  Invasive.org  Go Botany  NRCS-2
Acer pseudoplatanus Sycamore maple (P) Tree  Yes PA DCNR; USFS  Invasive.org  Go Botany
Aegopodium podagraria Goutweed/Bishops Weed  Herbaceous  Yes PCA; USFS  Invasive.org  Go Botany NRCS-1
Ailanthus altissima Tree of heaven  Tree  Yes  PA DCNR; PCA  Invasive.org  Go Botany NRCS-1 
Alliaria petiolata Garlic mustard  Herbaceous  Yes Maine; PA DCNR; PCA; TNC; UNH  Invasive.org  Go Botany  NRCS-2
Amorpha fruticosa False indigo (P)  Shrub Yes  Invasive.org  Go Botany
Ampelopsis brevipedunculata Porcelainberry  Woody Vine N/A Maine; PA DCNR; PCA  Invasive.org  Go Botany  NRCS-2
Artemisia vulgaris Mugwort Herbaceous N/A  Invasive.org  Go Botany NRCS-2 
Arthraxon hispidus Hairy jointgrass (P)  Grass or Grass-like  Yes PA DCNR  Invasive.org  Go Botany
Bassia scoparia Common kochia (P) Herbaceous  Yes NRCS  Invasive.org  Go Botany
Berberis thunbergii Japanese barberry  Shrub  N/A DEEP; Maine; PA DCNR; PCA  Invasive.org  Go Botany NRCS-1;  NRCS-2
Berberis vulgaris Common barberry  Shrub Yes  NRCS; PA DCNR  Invasive.org  Go Botany
Bromus tectorum Drooping brome-grass (P)  Grass or Grass-like Yes NRCS; PA DCNR  Invasive.org  Go Botany
Butomus umbellatus Flowering rush (P)  Aquatic & Wetland Yes CAES; MIPN; Montana; USFS  Invasive.org  Go Botany
Cabomba caroliniana Fanwort  Aquatic & Wetland Yes CAES; Maine; PA DCNR; RI DEM  Invasive.org  Go Botany
Callitriche stagnalis Pond water-starwort (P)  Aquatic & Wetland Yes CAES  Invasive.org  Go Botany
Cardamine impatiens Narrowleaf bittercress  Herbaceous  Yes PA DCNR  Invasive.org  Go Botany NRCS-2
Carex kobomugi Japanese sedge (P) Grass or Grass-like  Yes  PCA  Invasive.org  Go Botany  NRCS-2
Celastrus orbiculatus Oriental bittersweet  Woody Vine Yes Maine; NRCSPCA; PA DCNR; TNC; TNC (VT)  Invasive.org  Go Botany NRCS-1
Centaurea stoebe Spotted knapweed  Herbaceous  Yes NRCS; PA DCNR; PCA  Invasive.org  Go Botany NRCS-1
Cirsium arvense Canada thistle (P)  Herbaceous  Yes PA DCNR; PCA  Invasive.org  Go Botany NRCS-2
Cynanchum louiseae Black swallow-wort  Herbaceous  Yes Maine; PA DCNR; PCA Invasive.org  Go Botany NRCS-1
Cynanchum rossicum Pale swallow-wort  Herbaceous  Yes  PA DCNR; PCA; USFS Invasive.org  Go Botany NRCS-1
Datura stramonium Jimsonweed (P)  Herbaceous  Yes  PA DCNR Invasive.org  Go Botany
Egeria densa Brazilian water-weed (P)  Aquatic & Wetland  Yes CAES; Maine; PA DCNR; RI DEM Invasive.org Photos  Go Botany NRCS-1
Eichhornia crassipes Common water-hyacinth (P)  Aquatic & Wetland N/A CAES; RI DEM; UF Invasive.org  Go Botany NRCS-2
Elaeagnus angustifolia Russian olive (P)  Shrub Yes Maine; PA DCNR; PCA Invasive.org  Go Botany NRCS-1NRCS-2
Elaeagnus umbellata Autumn olive  Shrub Yes CIPWG; DEEP; Maine; NRCS; PA DCNR Invasive.org  Go Botany NRCS-1NRCS-2
Elsholtzia ciliata Crested late-summer mint (P)  Herbaceous Yes IPANE Invasive.org  Go Botany
Euonymus alatus Winged euonymus  Shrub N/A CIPWG; NRCS; PA DCNR Invasive.org  Go Botany NRCS-1
Euphorbia cyparissias Cypress spurge (P)  Herbaceous Yes IPANE; USFS Invasive.org  Go Botany NRCS-1
Euphorbia esula Leafy spurge  Herbaceous  Yes  NRCS; PCA; USFS Invasive.org  Go Botany
Frangula alnus Glossy Buckthorn  Shrub  N/A DEEP; Maine; NRCS; PA DCNR; USFS  Invasive.org  Go Botany NRCS-1
Froelichia gracilis Slender snake cotton  Herbaceous  Yes IPANE  Invasive.org  Go Botany
Glechoma hederacea Ground ivy (P)  Herbaceous Yes  NRCS  Invasive.org  Go Botany
Glyceria maxima Reed mannagrass (P)  Grass or Grass-like Yes  IPANE  Invasive.org  Go Botany
Heracleum mantegazzianum Giant hogweed (P)  Herbaceous Yes  CIPWG; PA DCNR; USFS Invasive.org Photos  Go Botany
Hesperis matronalis Dame’s rocket  Herbaceous  Yes  PA DCNR; USFS Invasive.org  Go Botany  NRCS-1 
Humulus japonicus Japanese hops (P)  Herbaceous Yes  PA DCNR; PCA; USFS Invasive.org  Go Botany NRCS-2
Hydrilla verticillata Hydrilla  Aquatic & Wetland  Yes CAES; Maine; NRCS Invasive.org Photos  Go Botany  NRCS-2
Impatiens glandulifera Ornamental jewelweed (P)  Herbaceous Yes IPANE; WA NWCB Invasive.org  Go Botany NRCS-2
Iris pseudacorus Yellow iris  Aquatic & Wetland Yes CAES; CIPWG; NRCS; PA DCNR Invasive.org  Go Botany  NRCS-2
Lepidium latifolium Perennial pepperweed  Herbaceous Yes PCA; WA NWCB  Invasive.org  Go Botany
Ligustrum obtusifolium Border privet (P)  Shrub Yes PA DCNR; PCA  Invasive.org  Go Botany NRCS-2
Ligustrum ovalifolium California privet (P)  Shrub  N/A  PCA  Invasive.org  Go Botany NRCS-2
Ligustrum vulgare European privet (P)  Shrub  N/A PA DCNR; PCA  Invasive.org  Go Botany  NRCS-2
Lonicera japonica Japanese honeysuckle  Woody Vine Yes DEEP; Maine; PA DCNR; PCA; USFS  Invasive.org  Go Botany NRCS-1NRCS-2
Lonicera maackii Amur honeysuckle  Shrub Yes PA DCNR; PCA; TNC; USFS  Invasive.org  Go Botany  NRCS-2
Lonicera morrowii Morrow’s honeysuckle  Shrub Yes Maine; NRCS; PA DCNR; PCA; TNC; USFS  Invasive.org  Go Botany NRCS-2
Lonicera tatarica Tatarian honeysuckle (P)  Shrub Yes Maine; NRCS; PA DCNR; PCA; TNC; USFS Invasive.org  Go Botany  NRCS-2
Lonicera x bella Belle honeysuckle  Shrub Yes Maine; PA DCNR; PCA; TNC; Wisconsin Invasive.org NRCS-2
Lonicera xylosteum Dwarf honeysuckle (P)  Shrub Yes PCA; TNC Invasive.org  Go Botany NRCS-2
Lychnis flos-cuculi Ragged robin (P)  Herbaceous Yes  IPANE Invasive.org  Go Botany
Lysimachia nummularia Moneywort (P)  Herbaceous  N/A  PA DCNR; USFS Invasive.org  Go Botany
Lysimachia vulgaris Garden loosestrife (P)  Herbaceous Yes IPANE; UC-Davis; WA NWCB  Invasive.org  Go Botany
Lythrum salicaria Purple loosestrife  Aquatic & Wetland  Yes  CAES; Maine; NRCS; PA DCNR; PCA; TNC; UConn  Invasive.org  Go Botany  NRCS-1;  NRCS-2
Marsilea quadrifolia European waterclover (P)  Aquatic & Wetland  Yes CAES; IPANE  Invasive.org  Go Botany
Microstegium vimineum Japanese stilt grass  Grass or Grass-like  Yes Maine; PA DCNR; PCA; TNC; USFS  Invasive.org  Go Botany NRCS-1NRCS-2 
Miscanthus sinenesis Eulalia (P)  Grass or Grass-like N/A IPANE; PA DCNR; USFS  Invasive.org  Go Botany
Myosotis scorpioides Forget-me-not  Aquatic & Wetland  Yes CAES; IPANE  Invasive.org  Go Botany NRCS-2
Myriophyllum aquaticum Parrotfeather (P)  Aquatic & Wetland  Yes CAES; PA DCNR; RI DEM; WA NWCB Invasive.org  Go Botany NRCS-1NRCS-2
Myriophyllum heterophyllum Variable-leaf watermilfoil  Aquatic & Wetland Yes CAES;  RI DEM; WA NWCB Invasive.org  Go Botany NRCS-1
Myriophyllum spicatum Eurasian watermilfoil  Aquatic & Wetland Yes CAES; Maine; NRCS; PA DCNR; PCA; RI DEM; WA NWCB Invasive.org  Go Botany  NRCS-1
Najas minor Brittle water-nymph (P)  Aquatic & Wetland Yes  CAES; IPANE; RI DEM Invasive.org  Go Botany
Nasturtium microphyllum Onerow yellowcress (P)  Aquatic & Wetland Yes CAES; IPANE Invasive.org  Go Botany
Nasturtium officinale Watercress (P)  Aquatic & Wetland Yes CAES; WA NWCB Invasive.org  Go Botany
Nelumbo lutea American water lotus (P)  Aquatic & Wetland Yes CAES; RI DEM Invasive.org  Go Botany  NRCS-2
Nymphoides peltata Yellow floating heart (P)  Aquatic & Wetland Yes CAES; IPANE; RI DEM; WA NWCB Invasive.org  Go Botany
Onopordum acanthium Scotch thistle (P)  Herbaceous  Yes IPANE; WA NWCB  Invasive.org  Go Botany
Ornithogalum umbellatum Star-of-Bethlehem (P)  Herbaceous N/A IPANE; PA DCNR; PCA  Invasive.org  Go Botany
Paulownia tomentosa Princess tree (P)  Tree Yes  PA DCNR; PCA; USFS  Invasive.org  Go Botany
Phalaris arundinacea Reed canary grass  Grass or Grass-like N/A NRCS; PA DCNR; WA NWCB  Invasive.org  Go Botany NRCS-2
Phragmites australis Common reed  Grass or Grass-like  Yes Maine; NRCS; PCA; PA DCNR; TNC; USFS; WA NWCB  Invasive.org  Go Botany  NRCS-1NRCS-2
Pistia stratiotes Water lettuce (P)  Aquatic & Wetland  N/A  CAES; IPANE  Invasive.org
Poa compressa Canada bluegrass (P)  Grass or Grass-like  Yes IPANE; NRCS  Invasive.org  Go Botany
Polygonum caespitosum Bristled knotweed  Herbaceous  Yes IPANE  Invasive.org
Polygonum cuspidatum Japanese knotweed  Herbaceous Yes DEEPMaine; MI DNRNRCS; PA DCNR; PCA; TNC Invasive.org NRCS-2
Polygonum perfoliatum Mile-a-minute vine  Herbaceous Yes CIPWG; Maine; NRCS; PCA; UConn; USFS Invasive.org Photos  Go Botany NRCS-1;  NRCS-2
Polygonum sachalinense Giant knotweed (P)  Herbaceous Yes PA DCNR; WA NWCB Invasive.org  Go Botany
Populus alba White poplar (P)  Tree Yes IPANE; PCA Invasive.org  Go Botany
Potamogeton crispus Crispy-leaved pondweed  Aquatic & Wetland Yes CAES; NRCS; PA DCNR; RI DEM; WA NWCB Invasive.org  Go Botany  NRCS-1
Pueraria montana Kudzu (P)  Woody Vine Yes PA DCNR; PCA; USFS; WA NWCB Invasive.org Photos  Go Botany NRCS-2
Ranunculus ficaria Fig buttercup  Herbaceous Yes  PCA  Invasive.org NRCS-2
Rhamnus cathartica Common buckthorn  Shrub  Yes Maine; NRCS; PA DCNR; PCA; USFS Invasive.org  Go Botany  NRCS-1
Robinia pseudoacacia Black locust  Tree  N/A NRCS; PCA Invasive.org  Go Botany NRCS-1
Rosa multiflora Multiflora rose  Shrub  Yes DEEP; Maine; NRCS; PA DCNR; PCA; TNC Invasive.org  Go Botany NRCS-1NRCS-2
Rosa rugosa Rugosa rose (P)  Shrub N/A  NRCS Invasive.org  Go Botany
Rubus phoenicolasius Wineberry  Shrub  Yes PA DCNR; PCA; USFS  Invasive.org  Go Botany
Rumex acetosella Sheep sorrel (P)  Herbaceous  Yes  USFS  Invasive.org  Go Botany
Salvinia molesta Giant salvinia (P)  Aquatic & Wetland  Yes CAES; IPANE; PCA  Invasive.org  Go Botany
Senecio jacobaea Tansy ragwort (P)  Herbaceous Yes IPANE; WA NWCB  Invasive.org  Go Botany
Silphium perfoliatum Cup plant (P)  Herbaceous Yes  NRCS Invasive.org  Go Botany
Solanum dulcamara Bittersweet nightshade (P)  Herbaceous Yes  IPANE; USFS  Invasive.org  Go Botany
Trapa natans Water chestnut  Aquatic & Wetland Yes CAES; Maine; PA DCNR; PCA; RI DEM  Invasive.org  Go Botany  NRCS-1; NRCS-2
Tussilago farfara Coltsfoot  Herbaceous Yes  IPANE; USFS; WA NWCB  Invasive.org  Go Botany
Valeriana officinalis Garden heliotrope (P)  Herbaceous Yes IPANE; USFS  Invasive.org  Go Botany

*CAES= Connecticut Agricultural Experiment Station CIPWG= Connecticut Invasive Plant Working Group DEEP= Connecticut Department of Energy and Environmental Protection IPANE= Invasive Plant Atlas of New England Maine= University of Maine Cooperative Extension MIPN= Midwest Invasive Plant Network Montana= Montana State University Extension NRCS= Natural Resource Conservation Service, United States Department of Agriculture PCA= Plant Conservation Alliance, National Park Service PA DCNR= Pennsylvania Department of Conservation and Natural Resources RI DEM= RIsland Department of Environmental Management TNC= The Nature Conservancy UC-Davis= University of California-Davis, Cooperative Extension & Agricultural Experiment Station  USFS= US Forest Service, United States Department of Agriculture UF= University of Florida Extension UNH= University of New Hampshire Extension WA NWCB= Washington State Noxious Weed Control Board