Plants regulated by the federal government are largely those that impact agriculture and are regulated as contaminants of seed. Very few invasive ornamental plants are regulated despite the many threats they pose to our economy, environment, and human health.
Regulations vary greatly by jurisdiction, with several provinces and territories having no regulations. Overall, there are 238 plants regulated by Canada and the provinces. The US border states regulate over 500 plants and include many more ornamental plants.
We compiled a list of high-risk plants currently regulated in parts of Canada and in the 13 US Border States. We have added lists of high-risk aquatic plants identified by the Department of Fisheries and Oceans and compared these lists to the plants that currently appear in the Canadian Food Inspection Agency (CFIA) Weed Risk Assessment documents. Based on these lists, we have identified over 90 high-priority plants that should be assessed or reassessed by the CFIA. Here is the file containing those spreadsheets (download here). (As we have likely made errors in the arduous compilation process, you can confirm data using the primary sources found on our Province and territory regulations page and State regulations page.
Additionally there are many invasive ornamental plants that are not currently regulated. Some of those appear on the lists developed by plant councils below. Some of the ornamental terrestrial and aquatic invasive plants currently identified by invasive plants councils across Canada and or included in the Invasive Alien Plants in Canada – Technical Report are listed below.
This is a partial list of known threats across Canada as identified by Canadian authorities and plants that are regulated by multiple states bordering Canada (indicated by bold type face):
A
- Alder, European black (Alnus glutinosa)
- Angelica, woodland (Angelica sylvestris)
- Arrowhead, giant (Sagittaria sagittifolia)
B
- Baby’s-breath (Gypsophila paniculata)
- Balsam — Himalayan & small-flower (Impatiens glandulifera, I. parviflora)
- Barberry — Japanese & common (Berberis thunbergii, B. vulgaris)
- Bellflower, creeping (Campanula rapunculoides)
- Bittersweet, oriental (Celastrus orbiculatus)
- Blackberry, wild complex (Rubus fruticosus)
- Buckthorn, common (Rhamnus cathartica)
- Buckthorn, glossy (Frangula alnus)
- Bulrush, rice-field (Schoenoplectiella mucronata)
- Broom, Scotch (Cytisus scoparius)
- Butterfly bush (Buddleja davidii)
C
- Cattail — narrow-leaf & hybrid (Typha angustifolia, T. × glauca)
- Celandine, lesser (Pilewort) (Ranunculus ficaria)
- Cherry, European bird (Prunus padus)
- Chervil, wild (Anthriscus sylvestris)
- Cinquefoil, sulphur (Potentilla recta)
- Clematis, yellow (Clematis tangutica)
- Clover, white sweet (Melilotus alba)
- Cogongrass (Imperata cylindrica, I. brasiliensis)
- Comfrey (Symphytum officinale)
- Cork tree, Amur (Phellodendron amurense)
- Creeping Jenny (Lysimachia nummularia)
- Crassula, swamp (Australian) (Crassula helmsii)
- Curly-leaf pondweed (Potamogeton crispus)
D
- Daisy, oxeye (Leucanthemum vulgare)
- Dame’s rocket (Hesperis matronalis)
- Daylily, common (Hemerocallis fulva)
- Duck lettuce (Ottelia alismoides)
- Dyer’s woad (Isatis tinctoria)
E
- Eel-grass (Vallisneria spiralis)
- Elodea, Brazilian (Egeria densa)
- Euonymus — winged & winter-creeper (Euonymus alatus, E. fortunei)
- European water-clover (Marsilea quadrifolia)
- European water-lily (Nymphaea alba)
F
- Fanwort, Carolina (Cabomba caroliniana)
- Flatsedge (Cyperus difformis)
- Floating-heart, yellow (Nymphoides peltata)
- Flowering rush (Butomus umbellatus)
- Foxglove (Digitalis purpurea)
- Frog-bit — European & American (Hydrocharis morsus-ranae, H. spongia)
G
- Garlic mustard (Alliaria petiolata)
- Goutweed (Aegopodium podagraria)
- Grass, canary reed (Phalaris arundinacea)
- Grass, miscanthus (Miscanthus sinensis, M. sacchariflorus)
- Grass, torpedograss (Panicum repens)
- Ground-ivy / Bugleweed (Ajuga reptans)
H
- Hawkweed, orange (Pilosella aurantiaca)
- Hawkweeds, introduced spp. (Hieracium spp.)
- Hogweed, giant (Heracleum mantegazzianum)
- Holly, English (Ilex aquifolium)
- Honeysuckles — Japanese, Amur, Morrow’s, Tatarian, Bell’s & fly (Lonicera japonica, L. maackii, L. morrowii, L. tatarica, L. × bella, L. xylosteum)
- Hound’s-tongue (Cynoglossum officinale)
- Hydrilla (Hydrilla verticillata)
- Hygrophila, East Indian (Hygrophila polysperma)
- Hyacinth, water (Eichhornia crassipes)
I
- Iris, yellow-flag (Iris pseudacorus)
- Ivy, English (Hedera helix)
K
- Knapweeds — bachelor’s buttons, big & mountain bluet (Centaurea cyanus, C. macrocephala, C. montana)
- Knotweed, Himalayan (Persicaria wallichii)
- Knotweeds — Japanese, giant & Bohemian (Reynoutria japonica, R. sachalinensis, R. × bohemica)
L
- Lamium — yellow archangel & purple (Lamium galeobdolon, L. purpureum)
- Lady’s mantle (Alchemilla mollis)
- Locust, black (Robinia pseudoacacia)
- Loosestrife, purple & wand (Lythrum salicaria, L. virgatum)
M
- Mannagrass — floating & great (Glyceria fluitans, G. maxima)
- Maples — Amur, Norway & sycamore (Acer ginnala, A. platanoides, A. pseudoplatanus)
- Miscanthus grasses (Miscanthus sinensis, M. sacchariflorus) → also listed under G for ease of search
- Mosquito-fern, pinnate (Azolla pinnata)
- Mountain-ash, European (Sorbus aucuparia)
- Mulberry, white (Morus alba)
N
- Nasturtium / Yellowcress, water (Nasturtium officinale)
- Nymph, brittle water-nymph (Najas minor)
O
- Olive — Russian & autumn (Elaeagnus angustifolia, E. umbellata)
- Oxygen-weed, African (Lagarosiphon major)
P
- Peashrub, Siberian (Caragana arborescens)
- Pear, Callery (Pyrus calleryana)
- Periwinkle (Vinca major, V. minor)
- Phragmites / Common reed (non-native) (Phragmites australis subsp. australis)
- Pine, Scotch (Pinus sylvestris)
- Pilewort / lesser celandine (Ranunculus ficaria)
- Poplar, silver (Populus alba)
- Porcelainberry (Ampelopsis glandulosa)
- Privet, border (Ligustrum obtusifolium)
R
- Reed canary-grass (Phalaris arundinacea) → see also G
- Rose — multiflora & rugosa (Rosa multiflora, R. rugosa)
S
- Salvinia — giant & common (Salvinia auriculata, S. biloba, S. minima, S. molesta, S. natans)
- Sea-buckthorn (Hippophae rhamnoides)
- Smartweed, marsh-pepper (Persicaria hydropiper)
- Spirea, false (Sorbaria sorbifolia)
- Spurge-laurel (Daphne laureola)
- Spurges — leafy, myrtle & cypress (Euphorbia esula, E. myrsinites, E. cyparissias)
- Star-of-Bethlehem (Ornithogalum nutans)
- Stonecrop, goldmoss (Sedum acre)
- Stonewort, starry (Nitellopsis obtusa)
- Swallow-worts / dog-strangling vines — black & pale (Vincetoxicum nigrum, V. rossicum, Cynanchum louiseae)
- Sweet flag, European (Acorus calamus)
- Swamp crassula (Australian) (Crassula helmsii)
- Sycamore maple — see Maples
T
- Tamarisk / salt-cedar (Tamarix ramosissima, T. chinensis, T. parviflora & hybrids)
- Tansy, common (Tanacetum vulgare)
- Toadflax (Linaria dalmatica, L. vulgaris, L. genistifolia subsp. dalmatica)
- Tree-of-heaven (Ailanthus altissima)
V
- Valerian, common (Valeriana officinalis)
- Velvetleaf (Abutilon theophrasti)
- Viper’s-bugloss (Echium vulgare)
W
- Water chestnut, European (Trapa natans)
- Water-clover, European (Marsilea quadrifolia)
- Water-hyacinth (Eichhornia crassipes)
- Water lettuce (Pistia stratiotes)
- Water-lily, European (Nymphaea alba)
- Water-milfoils — parrot-feather, Eurasian & two-leaf (Myriophyllum aquaticum, M. spicatum, M. heterophyllum)
- Water poppy (Hydrocleys nymphoides)
- Water soldier (Stratiotes aloides)
- Water-nymph, brittle (Najas minor)
- Water-poppy (Hydrocleys nymphoides)
- Water-soldier (Stratiotes aloides)
- Wildflower mixes (often contain one or more invasive species — check seed lists carefully!)
Z
- (— none at this time —)
Plant lists and councils:
Canada
- Invasive Canada formerly The Canadian Council on Invasive Species https://canadainvasives.ca
- Invasive Species Centre (ISC) Plant Lists
- Canadian Council on Invasive Species CANADA’S UNWANTED INVASIVE PLANTS
- Invasive Species regulated under the Plant Protect Act
- Noxious Weeds regulated under the Weed Seeds Order
Alberta:
- Alberta Invasive Council Grow Me Instead
- Invasive Plants of Alberta 4th Edition 2022
- Alberta Invasive Plant Identification GUIDE: Prohibited Noxious and Noxious Weeds
Atlantic Canada:
- New Brunswick Council of Invasive Species www.nbala.ca/new-brunswick-council-of-invasive-species
- Nova Scotia/New Brunswick Plant Wise
- Nova Scotia Invasive Species Council Invasive Species List
- Newfoundland and Labrador – Exotic and Invasive Alien Speices in Newfoundland and Labrador (pdf)
- PEI Invasive Species Council Invasive Plant Lists
British Columbia:
- BC Invasive Terrestrial Plant List
- BC Invasive Species Council Grow Me Instead
- Official BC Ministry of Forests invasive species list
- InvasivesBC database, map and mobile data collection application
Manitoba:
- Manitoba Master Gardeners Invasive Plants
- Manitoba Invasive Species Council Grow Me Instead (pdf)
Ontario:
- Ontario Weed Control Act, (R.S.O. 1990, c. W.5) controls plants that are negatively impacting agriculture and horticulture lands. Currently there are 25 species designated noxious weeds in Ontario. This is a complaint driven act. Ontario Noxious Weeds posted by the Ministry of Agriculture food and Rural.
- Ontario Invasive Species Act https://www.ontario.ca/laws/regulation/160354 Scroll to bottom from prohibited and restricted plant lists. Note that no person shall propagate, buy, sell, trade or offer to buy, sell, lease or trade a prohibited and restricted invasive plants.
- Ontario Invasive Aquatic Plant List https://www.ontario.ca/page/invasive-aquatic-plants
- Auditor General of Ontario – Value for Money Audit (2022)
- MidWest Invasive Plant List – https://mipn.org/invasive-plant-list/ (2024 in progress)
- Credit Valley Conservation Invasive Plant List (2021)
- Ontario Invasive Plant Council Grow Me Instead; Ontario Invasive Species Awareness
- Ontario Federation of Anglers and Hunters in partnership with Ontario Ministry of Natural Resources, Credit Valley Conservation – Appendix to A Landowner’s Guide to Managing and Controlling Invasive Plants in Ontario (2014)
- Upper Thames Conservation Invasive Non-native plants
- Ontario South Central Conservation Authorities Invasive plants (collated from member websites 2023)
- Ontario Society for Ecological Restoration – Invasive Exotic Species Ranking for Southern Ontario (2025, pdf)
Northwest Territories:
- Northwest Territories – Invasive and Alien Species Information Page; A Risk Assessment of Invasive Alien Species in the NWT
- NWT Stop the Spread
Nunavut:
- Nunavut – Non-native invasive species in Nunavut (Poster)
Saskatchewan:
- Saskatchewan Invasive Species Council Invasive Plant Fact Sheets
Yukon:
- Yukon Invasive Species Council Grow Me Instead (pdf)
North America:
- AKEPIC (Alaska Exotic Plant Information Center)
- Invasive Plant Atlas (US and Canada) Plant Species Reported to be Invasive in Natural Areas (1405 Records, 2018)
- Plant Invaders of Mid-Atlantic Natural Areas (Swearingen, J., B. Slattery, K. Reshetiloff, and S. Zwicker. 2010. Plant Invaders of Mid-Atlantic Natural Areas, 4th ed. National Park Service and U.S. Fish and Wildlife Service. Washington, DC. 168pp.)
- U.S. Invasive Plant Atlas
- Mid-Atlantic Invasive Network Invasive Plant List
Public Gardens as Sentinels of Invasive Plants Dashboard - Regional Invasive Species & Climate Change (RISCC) Management Networks
International:
- CABI Invasive Species Compendium https://bplant.org/website/14
- InvaCost https://www.invasivespeciescentre.ca/invacost-the-cost-of-invasive-species/
- Global Invasive Species Database 100 world’s worst species
- EU Invasive alien species of Union concern