Plants that have been assessed and categorized by the Rhode Island Invasive Species Council, as of 2/28/2001
- This list is for informational purposes only; it has no legal or regulatory stature.
- The list does NOT include every plant that is invasive in Rhode Island, but is a list of those plants that have been assessed to date, using the established criteria.
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Widespread and Invasive
| Cabomba caroliniana |
Fanwort |
| Celastrus orbiculatus |
Asiatic Bittersweet |
| Elaeagnus umbellata |
Autumn Olive |
| Lonicera japonica |
Japanese Honeysuckle |
| Lythrum salicaria |
Purple Loosestrife |
| Polygonum cuspidatum [= Fallopia japonica] |
Japanese Knotweed |
| Potamogeton crispus |
Curly Pondweed |
| Rhamnus cathartica |
Common Buckthorn |
| Rosa multiflora |
Multiflora Rose |
| Vincetoxicum nigrum [= Cynanchum nigrum] |
Black Swallowwort |
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Restricted and Invasive
| Ailanthus altissima (a) |
Tree of Heaven |
| Alliaria petiolata(a) |
Garlic Mustard |
| Ampelopsis brevipedunculata |
Porcelain-berry |
| Myriophyllum heterophyllum |
Variable Water-milfoil |
| Ranunculus ficaria |
Lesser Celandine |
| Rorippa nasturtium-aquaticum |
Watercress |
| Rubus phoenicolasius (b) |
Wineberry |
| Vincetoxicum rossicum [= Cynanchum rossicum] |
White Swallowwort |
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| Acer platanoides (b) |
Norway Maple |
| Berberis thunbergii (b) |
Japanese Barberry |
| Euonymus alatus (b) |
Burning Bush |
| Lonicera morrowii and Lonicera x Bella (b) |
Morrow and Bella Honeysuckle |
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Needs more research and observation/monitoring
Many of these species are known to be invasive in neighboring states.
| Acer pseudoplatanus |
Sycamore Maple |
| Allium vineale |
Field-garlic |
| Berberis vulgaris |
European Barberry |
| Campsis radicans |
Trumpet Creeper |
| Clematis terniflora [= C. paniculata] |
Autumn Clematis |
| Cytisus scoparius |
Scotch Broom |
| Daucus carota |
Queen Anne’s Lace |
| Elaeagnus angustifolia |
Russian Olive |
| Euonymus fortunei |
Winter Creeper |
| Hesperis matronalis |
Dame’s Rocket |
| Iris pseudoacorus |
Yellow Flag |
| Kochia scoparia |
Summer Cypress |
| Ligustrum species (d) |
Privet |
| Miscanthus sinensis |
Eulalia |
| Morus alba |
White Mulberry |
| Myosotis scropioides |
True Forget-me-not |
| Phellodendron japonicum |
Amur Corktree |
| Phragmites australis (e) |
Common Reed |
| Pinus thunbergiana |
Japanese Black Pine |
| Polygonum sachalinense |
Princess Feather |
| Quercus robur |
English Oak |
| Rhamnus frangula [ = Frangula alnus] (d) |
Glossy Buckthorn |
| Robinia pseudoacacia |
Black Locust |
| Rosa rugosa (f) |
Beach Rose |
| Yucca filamentosa |
Spanish Bayonet |
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Potentially Invasive Species
These are invasive in other states but have not yet become so in Rhode Island.
| Egeria densa [= Elodea densa] (g) |
Brazilian Waterweed |
| Hydrilla verticillata (h) |
Hydrilla |
| Lysimachia nummularia (i) |
Moneywort |
| Microstegium vimineum (j) |
Japanese Stiltgrass |
| Myriophyllum spicatum (h) |
Eurasian Water-milfoil |
| Najas minor (h) |
Eutrophic Water-nymph |
| Pistia stratiotes (k) |
Water-lettuce |
| Polygonum perfoliatum (l) |
Mile-a-minute Weed |
| Trapa natans (h) |
Water-chestnut |
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Weedy
Plants of disturbed areas; do not appear to be affecting minimally managed habitats. This list is not even close to all the non-native “weedy” plants in Rhode Island. The ones below were in the original list assessed by the RIISC during 2000; if a plant wasn’t on that list or wasn’t brought up subsequently as potentially meeting the criteria for an invasive species in the state, it is not included here.
| Aegopodium podagraria |
Goutweed |
| Bromus tectorum |
Drooping Brome Grass |
| Centaurea nigra, C. dubia, C. maculosa, etc. |
Knapweeds |
| Cirsium arvense |
Canada Thistle |
| Cirsium vulgare |
Bull Thistle |
| Coronilla varia |
Crown Vetch |
| Euphorbia cyparissias |
Cypress Spurge |
| Glechoma hederacea |
Ground Ivy |
| Lamium amplexicaule |
Henbit |
| Lamium purpureum |
Purple Dead-nettle |
| Rumex acetosella |
Sheep Sorrel |
| Solanum dulcamara |
European Nightshade |
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| a |
Spreading |
| b |
need more information on its spread in RI |
| c |
fits Criteria 1–9 and is widespread; need to assess reproductive capabilities of cultivars and hybrids |
| d |
fits Criteria 1–5 and is spreading; we need to know which species are the ones that naturalize and spread |
| e |
assessing locations of native non-aggressive populations |
| f |
fits Criteria 1–9; suggested “fast-track” monitoring |
| g |
12/2005: known from one site in the state |
| h |
12/2005: not yet confirmed in RI |
| i |
reported from RI but not assessed as invasive as of 12/2005 |
| j |
“Restricted + invasive” in CT; reported in several RI sites in summer 2005 |
| k |
12/2005: reported in RI waters but has not yet been found to survive winter |
| l |
12/2005: known from one site in the state where it is being controlled |
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