Canada: Province & Territories Plant Regulations

A spreadsheet of 238 plants regulated across Canada and an additional 320 plants regulated in the 13 U.S. States that border Canada (as of July 13, 2023) has been uploaded (it will download when clicked). There are likely errors in this spreadsheet, but links to the primary sources are below and on the USA: Border States Plant Regulations.

Links 1 – 14 jump to sections on this page. Other links open in new tab

  1. Canada
  2. Alberta
  3. British Columbia
  4. Manitoba
  5. New Brunswick
  6. Newfoundland and Labrador
  7. Northwest territories
  8. Nova Scotia
  9. Nunavut
  10. Ontario
  11. Prince Edward Island
  12. Quebec
  13. Saskatchewan
  14. Yukon
Federal, Provincial or Territorial LegislationNumber of Plant Taxa Regulated
CANADA (CAN)
Plant Protection Act (SC 1990, c. 22)
Seeds Act (R.S.C., 1985, c. S-8)		30 Federally Prohibited Taxa  
96 Noxious Weeds: 26 Class 1 Prohibited, 36 Class 2 Primary, 29 Class 3 Secondary, 5 Class 4 Secondary, 42 Class 5 (taxa are in other classes)  
ALBERTA (AB)
Weed Control Act (SA 2008, c.W-5.1)		80 Noxious Weeds: 44 prohibited, 29 noxious, 7 nuisance
16 aquatic invasive plants are regulated under the Alberta Fisheries Act
BRITISH COLUMBIA (BC)
Weed Control Act ([RSBC 1996] CHAPTER 487)
Spheres of Concurrent Jurisdiction – Environment and Wildlife Regulation, BC Reg. 144/200		66 Noxious Weeds: 39 provincial, 27 regional

Approximately 30 more taxa are regulated under the Environment and Wildlife Regulation
MANITOBA (MB)
Noxious Weeds Act (S.M. 2015, c.38)
Water Protection Act (C.C.S.M. c. W65) Aquatic Invasive Species Regulation		110 Noxious Weeds: 21 Tier 1 prohibited, 18 Tier 2 restricted, 50 Tier 3 (complaint controlled)
21 invasive aquatic plants prohibited
NEW BRUNSWICK (NB)
Weed Control Act (SNB 1969, C.21		No lists
NEWFOUNDLAND AND LABRADOR (NL)No lists
NORTHWEST TERRITORIES (NT)
Protected Areas Act (SNWT 2019, c. 11)		No lists
NOVA SCOTIA (NS)
Agricultural Weed Control Act (R.S.N.S. 1989, c. 501)		10 Noxious Weeds: 9 Class 1 threats to agricultural or cultivated land; 1 Class 2 threat to health
NUNAVUT (NU)
Wildlife Act (S.Nu. 2020, c.15)		“No person shall release a member of a species into a habitat in which that species does not belong or never naturally occurred.” Wildlife Act, SNu 2003, c 26
ONTARIO (ON)
Weed Control Act (R.S.O. 1990, c. W.5 Invasive Species Act (S.O. 2015, c.22)		25 Noxious Weeds
22 Invasive alien plants taxa: 6 prohibited taxa; 15 restricted
PRINCE EDWARD ISLAND (PE)
Weed Control Act (Chapter W-2-1) Purple Loosestrife Control Regulations		One taxa Lythrum spp.
QUEBEC (QC)
Agricultural Abuses Act (R.S.Q. c. A-2) repealed		Quebec is proposing to regulate 31 invasive plants. “QUÉBEC, le 22 oct. 2025 /CNW/ – Le ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs annonce le dépôt d’un projet de règlement visant à interdire la vente et la culture à des fins de distribution de 31 espèces exotiques envahissantes (EEE) floristiques.”
SASKATCHEWAN (SK)
Weed Control Act (Chapter W-11.1 2014, c.19)		60 Noxious Weeds: 23 prohibited, 37 noxious, and five nuisance weeds 
YUKON (YT)
Environmental Act (RSY 2002, c 76)		No lists
Table of Numbers of Regulated Taxa in Canada

Canada

Regulated Plant Lists:

Associated Policy, Legislation and Agreements

Alberta

Regulatory approach
Agriculture-focused weed legislation with a separate framework for aquatic species.
 Weed Control Act (SA 2008, c.W-5.1) and Fisheries (Alberta) Act, RSA 2000, c F-16

What is regulated

🌱 73 terrestrial plants Provincially Regulated Weeds
44 prohibited noxious weeds; 29 noxious weeds (eradication or control required once listed)

💧 16 aquatic invasive plants Aquatic Invasive Species
Regulated under fisheries legislation (possession, transport, and release prohibited under fisheries legislation)

Key limitations

  • Aquatic plants regulated outside the Weed Control Act with different restrictions
  • Taxonomic ambiguity and hybrid species complicate enforcement (McClay, 2012)
    • The knotweeds are one example of plants for which there is considerable taxonomic confusion and hybridization can make this complicated. Different provinces are using different nomenclature and some provinces seem unaware of hybrids.
  • Limited information on distribution and impacts

British Columbia

British Columbia (BC)

Regulatory approach
Provincial weed legislation with regional authority, Weed Control Act (RSBC 1996, C. 487). Regional regulation of certain additional plants are permitted under the Spheres of Concurrent Jurisdiction – Environment and Wildlife Regulation (B.C. Reg. 144/2004).

What is regulated

🌱 66 plants under the Weed Control Regulation (B.C. Reg. 66/85):

  • 39 species regulated province-wide
  • 27 additional species regulated at the regional level
  • 47 terrestrial plants are lists in Spheres of Concurrent Jurisdiction

💧 Some aquatic/semiaquatic invasive plants are included under the Weed Control Act (flowering rush, purple loosestrife, yellow flag iris); 8 aquatic plants are listed in Spheres of Concurrent Jurisdiction.

Key limitations

  • Regionalized authority results in uneven regulation and confusion across the province
  • Common-name listings in Spheres of Concurrent Jurisdiction create taxonomic ambiguity

Additional context

Manitoba

Manitoba (MB)

Regulatory approach
Tiered weed legislation for plants under the Noxious Weeds Act (S.M. 2015, c.38), combined with a strong aquatic invasive species regime under Water Protection Act – Aquatic Invasive Species Regulation (C.C.S.M. c. W65).

What is regulated

🌱 89 terrestrial plants specified in the Declaration Of Noxious Weeds

  • 21 Tier 1 (eradication required)
  • 18 Tier 2 (restricted)
  • 50 Tier 3 (complaint-controlled)

💧 21 aquatic invasive plants regulated under the Water Protection Act

Scope

  • Tier 1 weeds must be eradicated without conditions
  • Tier 2 and 3 weeds subject to conditional or complaint-driven control
  • Aquatic invasive plants: possession prohibited, effectively restricting transport and distribution

Key limitations

  • Only one knotweed species listed, despite widespread hybridization
  • Terrestrial invasive plant regulation remains agriculture-focused
  • Separate statutes govern terrestrial and aquatic invasive plants

New Brunswick

New Brunswick has a Weed Control Act (SNB 1969, C.21) but there are no plants regulated by species.

NB Weed Control Act https://www.canlii.org/en/nb/laws/astat/snb-1969-c-21/latest/snb-1969-c-21.html

NB Provincial legislation https://laws.gnb.ca/en/BrowseTitle?letter=A

New Brunswick Council of Invasive Species www.nbala.ca/new-brunswick-council-of-invasive-species – Our priority is effective stewardship, monitoring and environmental management practices to help educate our communities and protect the health of our lake ecosystems.

NB Call for Action https://www.ourcommons.ca/Content/Committee/421/FOPO/Brief/BR10451777/br-external/NewBrunswickInvasiveSpeciesCouncil-e.pdf

Newfoundland and Labrador

Newfoundland and Labrador There are no lists of prohibited plants and no regulations preventing the release of invasive plants into the wild. Newfoundland and Labrador hosted the two-day Exotic and Invasive Alien Species Workshop in 2008 including a review of legislation. At the time, gaps in regulations, gaps in knowledge, lack of resource availability, lack of standardized definitions were cited as problems. Regarding legislation, it was noted:

  • Most of the legislation reviewed federally and provincially was written before the IAS issue was elevated to what it is now.
  • Many acts both nationally and provincially deal with substances, and organisms which could be interpreted as invasive alien species.
  • Many of these Acts were written to deal with specific issues as they relate to an industry or human health (i.e., Plant Protection Acts). (Exotic Species Education Coordination and Policy Development Project 2006-2008)
  • They called for better inter-agency cooperation and consideration of legislation.

NF & L – Exotic and Invasive Alien Species in Newfoundland and Labrador Brochure: https://www.gov.nl.ca/ffa/files/wildlife-biodiversity-invasive-alien-species-exotic-species-brochure.pdf

Nova Scotia

Nova Scotia Agricultural Weed Control Act (R.S.N.S. 1989, c. 501) prohibits nine species designated as Class Number One plants, which pose threats to cultivated or pasture lands and includes native plants like common milkweed, Asclepias syriaca, and one Class Number Two entry, Thorn-apple, Datura spp., which is capable of inflicting ill health and is in the nursery trade, (Regulations – Weed Control, accessed on Oct 2022).

NS Agricultural Weed Control Act
https://www.novascotia.ca/Just/Regulations/regs/WControl.htm
https://nslegislature.ca/sites/default/files/legc/statutes/agrcweed.htm https://nslegislature.ca/legc/bills/61st_2nd/1st_read/b109.htm

NS Control Regulations (Reg. 57/68) https://www.ecolex.org/details/legislation/weed-control-regulations-ns-reg-5768-lex-faoc096289/
NS Fisheries and Coastal Resources Act https://novascotia.ca/natr/biodiversity/pdf/Biodiversity_AlienSpecies_Apr25.pdf
NS Weed Control Regulations: http://extwprlegs1.fao.org/docs/pdf/ns96289.pdf
List of weeds replaced: O.I.C. 2003-536, N.S. Reg. 219/2003.
https://novascotia.ca/just/regulations/regs/WControl.htm
Halifax Invasive Species on Watch List https://cdn.halifax.ca/sites/default/files/documents/about-the-city/energy-environment/InvasiveSpeciesinHalifax.pdf

Northwest Territories

The Northwest Territories have no regulation specifically prohibiting plants. There is a Protected Areas Act(SNWT 2019, c. 11) to support and promote the protection, conservation and maintenance of biodiversity, ecological integrity, and cultural continuity of the Northwest Territories through the creation of a representative network of protected areas intended to be permanent of the benefit of current and future generations. It may be possible through this act to undertake protective measures, where there are threats of serious or irreparable harm to the ecological integrity of an area posed by invasive plant species. But federal policies and regulatory tools would be beneficial.

NWT Invasive SpeciesCouncil https://nwtcispp.ca

A Risk Assessment of Invasive Alien Species in the NWT https://www.enr.gov.nt.ca/sites/enr/files/reports/overview_on_ias_project.pdf

Invasive alien species NWT Information Page https://www.enr.gov.nt.ca/en/services/invasive-alien-species

NT Brochure https://www.enr.gov.nt.ca/sites/enr/files/brochures/invaders_in_nwt.pdf

Report on the 2016 Survey of Exotic Plants along Northwest Territories Highways https://www.enr.gov.nt.ca/sites/enr/files/resources/report_on_the_2016_survey_of_exotic_plants_along_northwest_territories_h.pdf

A Risk Assessment of Invasive Alien Species in the NWT S. Carrière https://www.enr.gov.nt.ca/sites/enr/files/reports/overview_on_ias_project.pdf

Nunavut

In Nunavut, The Wildlife Act (S.Nu. 2020, c.15) establishes a comprehensive regime for the management of wildlife and habitat …, including the conservation, protection, and recovery of species at risk. It specifically refers to Invasive species. “No person shall release a member of a species into a habitat in which that species does not belong or never naturally occurred.”  A guiding principle, Avatimik Kamattiarniq/Amiginik Avatimik, means that “people are stewards of the environment and must treat all of nature holistically and with respect, because humans, wildlife and habitat are inter-connected and each person’s actions and intentions towards everything else have consequences, for good or ill.”  17 non-native plants have been identified, but as of 2010, “there are currently no known species in Nunavut that can be classified as aquatic or terrestrial invasive species, (Environment Canada, Non-Native & Invasive species in Nunvut, 2010). However, Fallopia sachalinensis (giant knotweed) and Lythrum salicaria (purple loosestrife) are among invasive plants reported in Nunavut on CABI Invasive Species Compendium.

Non-native invasive species in Nunavut (poster) https://www.gov.nu.ca/environment/documents/non-native-invasive-species-nunavut-poster

Ontario

Ontario is the only province with an explicit statute to address IAPS, the Invasive Species Act, (S.O. 2015, c.22).  It specifically has provisions to regulate a species “harming or is likely to harm the natural environment of Ontario, regardless of whether it is present in Ontario or in a part of Ontario.” It is illegal to import, possess, deposit, release, transport, breed/grow, buy, sell, lease or trade prohibited invasive species. There are currently five prohibited aquatic invasive plants on the list: Brazilian Elodea Egeria densa, European Water Chestnut Trapa natans, Hydrilla Hydrilla verticillata, Parrot Feather Myriophyllum aquaticum, Water Soldier Stratiotes aloides. There are an additional three restricted aquatic species, which are already present: Fanwort (Cabomba caroliniana), European frog-bit (Hydrocharis morsus-ranae), and Yellow Floating Heart (Nympoides pelata).  Four knotweeds are on the restricted list, though Ontario uses different scientific nomenclature than the western provinces: Giant Knotweed (Reynoutria sachalinensis), Himalayan Knotweed (Koenigia polystachya), Japanese Knotweed (Reynoutria japonica) as well as the hybrid Bohemian knotweed (Reynoutria ×bohemica).

In addition, the 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 Affairs contained only common names and no scientific names (as of June 2023), making listings like daylily ambiguous.

Ontario Invasive Species Act Prohibited Plants https://www.ontario.ca/laws/regulation/160354

New restricted species https://ero.ontario.ca/notice/019-3465

Removal of Aquatic Invasive plants is permitted in accordance with rules explained here https://www.ontario.ca/page/invasive-aquatic-plants https://www.ontario.ca/page/remove-invasive-aquatic-plants (This is not particularly clear).

Invasive Species Act, 2015, S.O. 2015, c. 22 https://www.canlii.org/en/on/laws/regu/o-reg-354-16/latest/o-reg-354-16.html

Ontario Invasive Aquatic Plant List https://www.ontario.ca/page/invasive-aquatic-plants

Weed Control Act, RSO 1990, c W.5, <https://canlii.ca/t/kpjc> retrieved on 2022-03-11

Conservation Authorities Support New Invasive Species Act (2015). https://lprca.on.ca/2015/11/05/conservation-authorities-support-new-invasive-species-act/

Prince Edward Island

Prince Edward Island’s Weed Control Act (Chapter W-2-1) allows for the regulation of plants deemed noxious weeds. The Lieutenant Governor may designate a noxious weed as any plant that adversely affects or is likely to adversely affect any person, crop or other desirable plant, animal or property. Purple loosestrife (Lythrum salicaria) is the only specifically regulated species, (Purple Loosestrife Control Regulations https://www.princeedwardisland.ca/sites/default/files/legislation/W%2602-1-Weed%20Control%20Act%20Purple%20Loosestrife%20Control%20Regulations.pd ).

PEI Weed Control Act https://www.princeedwardisland.ca/sites/default/files/legislation/w-02-1-weed_control_act.pdf

WEED CONTROL ACT PURPLE LOOSESTRIFE CONTROL REGULATIONShttps://www.princeedwardisland.ca/sites/default/files/legislation/W%2602-1-Weed%20Control%20Act%20Purple%20Loosestrife%20Control%20Regulations.pdf

PEI Invasive Plant and Animal Species https://www.princeedwardisland.ca/en/information/environment-energy-and-climate-action/invasive-plant-and-animal-species

PEI Invasive Plant Council https://peiinvasives.com

Quebec

Quebec is proposing to regulate 31 invasive plants. “QUÉBEC, le 22 oct. 2025 /CNW/ – Le ministère de l’Environnement, de la Lutte contre les changements climatiques, de la Faune et des Parcs annonce le dépôt d’un projet de règlement visant à interdire la vente et la culture à des fins de distribution de 31 espèces exotiques envahissantes (EEE) floristiques.” Proposed Regulation

  • Aegopodium podagraria — Goutweed — Égopode podagraire
  • Alliaria petiolata — Garlic mustard — Alliaire officinale
  • Berberis thunbergii — Japanese barberry — Épine-vinette du Japon
  • Cabomba caroliniana — Carolina fanwort — Cabomba de Caroline
  • Celastrus orbiculatus — Oriental bittersweet — Célastre asiatique
  • Elaeagnus umbellata — Autumn olive — Oléastre à ombelles
  • Egeria densa — Brazilian waterweed — Élodée dense
  • Ficaria verna — Lesser celandine — Renoncule ficaire
  • Frangula alnus — Glossy buckthorn — Nerprun bourdaine
  • Heracleum mantegazzianum — Giant hogweed — Berce du Caucase
  • Heracleum sphondylium — Common hogweed — Berce commune (ou sphondyle)
  • Hydrilla verticillata — Hydrilla — Hydrille verticillée
  • Hydrocharis morsus-ranae — European frogbit — Hydrocharide grenouillette
  • Impatiens glandulifera — Himalayan balsam — Impatiente glanduleuse
  • Lonicera maackii — Amur honeysuckle — Chèvrefeuille de Maack
  • Microstegium vimineum — Japanese stiltgrass — Microstégie en osier
  • Myriophyllum aquaticum — Parrot’s feather — Myriophylle aquatique
  • Myriophyllum spicatum — Eurasian water-milfoil — Myriophylle à épis
  • Najas minor — Brittle naiad — Petite naïade
  • Nymphoides peltata — Yellow floating heart — Faux-nymphéa pelté
  • Phragmites australis subsp. australis — European common reed — Roseau commun (sous-espèce australis)
  • Potamogeton crispus — Curly-leaf pondweed — Potamot crépu
  • Pueraria montana — Kudzu — Kudzu
  • Reynoutria × bohemica — Bohemian knotweed — Renouée de Bohème
  • Reynoutria japonica — Japanese knotweed — Renouée du Japon
  • Reynoutria sachalinensis — Sakhalin knotweed — Renouée de Sakhaline
  • Rhamnus cathartica — Common buckthorn — Nerprun cathartique
  • Stratiotes aloides — Water soldier — Stratiote faux-aloès
  • Trapa natans — Water chestnut — Châtaigne d’eau
  • Vincetoxicum nigrum — Black swallow-wort — Dompte-venin noir
  • Vincetoxicum rossicum — Pale swallow-wort — Dompte-venin de Russie

Agricultural Abuses Act (R.S.Q. c. A-2). “Mauvaises herbes et plantes envahissantes.” The Act was repealed in 2018.
Les mauvaise herbes agricoles: https://issuu.com/craaq/docs/extraits-mauvaises_herbes_agricoles

Saskatchewan

Saskatchewan, Weed Control Act (Chapter W-11.1 2014, c.19) identifies 23 prohibited, 37 noxious and 5 nuisance weeds (plant list accessed October 7, 2022). Of the aquatic invasive plants, curly-leaves pondweed (Potamogeton crispus) flowering rush (Butomus umbellatus Eurasian watermilfoil (Myriophyllum spicatum) all tamarix are prohibted (Tamarix spp.) and yellow floating heart (Nymphoides peltata) are prohibited. No knotweeds are listed.

The Weed Control Act [clauses 2 (r), (s) and (w)] DESIGNATION OF PROHIBITED, NOXIOUS AND NUISANCE WEEDS https://www.npss.sk.ca/docs/2_pdf/The_Weed_Control_Act_-_Plant_List.pdfSK Aquatic Plants Nuisances http://www.saskh20.ca/DWBinder/epb47.pdf

The Fisheries Regulations prohibit Saskatchewan residents and visitors from importing, possessing, transporting or selling aquatic invasive species. https://www.saskatchewan.ca/government/news-and-media/2011/september/07/amendments-to-fisheries-regulations-protect-saskatchewan-waters The list of aquatic species does not include plants. https://www.saskatchewan.ca/residents/environment-public-health-and-safety/wildlife-issues/invasive-species/aquatic-species-not-allowed-in-saskatchewan

Yukon

The people of the Yukon have the right to a healthful environment and protect it with an Environmental Act(RSY 2002, c 76), which is a statute to ensure the maintenance of essential ecological processes and the preservation of biological diversity. It does not explicitly mention IAPS, but classifies “organisms prescribed by the Commissioner in Executive Council to be dangerous to life, health, property, or the natural environment” as Class 9 hazardous substances.

Yukon invasive species council: https://www.yukoninvasives.com/index.php/en/invasive-species/plants