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
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)  
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
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
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
Weed Control Act (SNB 1969, C.21
No lists
Protected Areas Act (SNWT 2019, c. 11)
No lists
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
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
Weed Control Act (R.S.O. 1990, c. W.5 Invasive Species Act (S.O. 2015, c.22)
25 Noxious Weeds
15 Invasive alien plants5 prohibited; 10 restricted
Weed Control Act (Chapter W-2-1) Purple Loosestrife Control Regulations
One taxa Lythrum spp.
Agricultural Abuses Act (R.S.Q. c. A-2) repealed
List no longer regulated
Weed Control Act (Chapter W-11.1 2014, c.19)
60 Noxious Weeds23 prohibited, 37 noxious, and five nuisance weeds 
Environmental Act (RSY 2002, c 76)
No lists
Table of Numbers of Regulated Taxa in Canada


International Plant Protection Convention (IPPC -1951)

North American Plant Protection Organization (NAPPO -1976)

Plant Protection Act (1990)

Convention on Biodiversity (1992)

Canada’s Biodiversity Strategy (1995)

World Trade Organization – Sanitary and Phytosanitary Measures, ‘SPS Agreement’ (1995)

Canadian Food Inspection Agency Act (1997)

IAS Strategy (2004)

Food and Agriculture Organization (FAO) of the United Nations. (2004). International standards for phytosanitary measures, PEST RISK ANALYSIS FOR QUARANTINE PESTS, INCLUDING ANALYSIS OF ENVIRONMENTAL RISKS AND LIVING MODIFIED ORGANISMS

New Initiatives in Canada’s Response to Invasive Plants (2008–2010)

Canada Invasive Plant Policy (CFIA, 2010).

2020 Biodiversity Goals and Targets (2016)

Aquatic Invasive Species Regulations (2015)
Canada Weed Seeds Order (2016)

Recommendations to Improve IAS Prevention and Management (2017)

2019 Spring Reports of the Commissioner of the Environment and Sustainable Development to the Parliament of Canada Report 1—Aquatic Invasive Species

Actual Regulated Plant Lists:

CFIA: Invasive Regulated Plants

Weed Seeds Order, 2016

Canada Weed Risk Analysis Documents


Alberta’s Weed Control Act (SA 2008, c.W-5.1) is administered by Agriculture, Forestry and Rural Economic Development and enables legislation for eradication and control of invasive plants. Regulated plants includes: 44 prohibited noxious weeds and another 29 noxious weeds that must be controlled, (Provincially Regulated Weeds, accessed October 7, 2022). Prohibited noxious weeds include ornamental plants like Japanese Knotweed (Fallopia japonica *) Giant knotweed (Fallopia sachalinensis*), Bohemian knotweed (Fallopia x bohemica*). The list also includes invasive aquatic ornamental plants like Eurasian watermilfoil (Myriophyllum spicatum), flowering rush (Butomus umbellatus), purple loosestrife (Lythrum salicaria), tamarisk species (Tamarix ramosissima, T. chinensis, T. parviflora), and yellow flag iris (Iris pseudacorus).

Issues that emerged during the process of revising the Weed Act included “taxonomic and nomenclatural complexities; a lack of information on species distribution and impacts; the lack of legal jurisdiction over aquatic species; the need for education and training of those involved in enforcing the Act,” (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.

Alberta Regulated Plants:

Aquatic Invasives

Fisheries (Alberta) Act, RSA 2000, c F-16

British Columbia

British Columbia’sWeed Control Act ([RSBC 1996] CHAPTER 487) prohibits 39 plants within all regions of the province and 27 more regionally (B.C. Reg. 66/85 Weed Control Regulation, accessed June 21, 2023). The provincewide list includes the three highly invasive knotweeds prohibited by Alberta, but an additional species listing for Himalayan knotweed (Polygonum polystachyum) is included. Of the invasive aquatics, Flowering rush purple loosestrife (Lythrum salicaria), and Yellow flag iris (Iris pseudacorus) are included.

There are additional plants regulated under B.C. Reg. 144/2004 SPHERES OF CONCURRENT JURISDICTION — ENVIRONMENT AND WILDLIFE REGULATION (Last amended July 26, 2021 by B.C. Reg. 219/2021) Unfortunately, they list common names only for many plants, which leads to some species confusion. For instance, saltcellar may refer to all plants in the Tamarix L. genus or one of several problematic species. Baby’s breath could refer to all plants in the Gypsophila genus, or to Gypsophila paniculata L. There are a number of areas of taxonomic confusion in the lists.

There are a number of proposed additions, which reflect concerns over certain aquatic invasive species and some emerging weedy species.   

British Columbia Provincial Weeds:

“The B.C. government has evaluated more than 320 terrestrial and aquatic plant species to determine likelihood of occurrence, establishment and spread as well as to determine which pose the greatest threat. Currently 45 plant species are candidates for early detection and rapid response activities, and an additional 109 species are recommended for other levels of management.”

B.C. Proposed Prohibited Noxious Weed List

B.C. Reg. 144/2004 SPHERES OF CONCURRENT JURISDICTION — ENVIRONMENT AND WILDLIFE REGULATION (Last amended July 26, 2021 by B.C. Reg. 219/2021)

BC Field Guide to Noxious and other Selected Invasive Plants

Invasive, Noxious and Alien Species of British Columbia – 2009 by Tanya Perzoff

Invasive Alien Species Framework for BC: Identifying and Addressing Threats to Biodiversity (PDF, 1.8MB)


Manitoba Noxious Weeds Act (S.M. 2015, c.38sets out requirements regarding control or destruction measures for different plants. They are categorized in tiers, with 21 Tier 1, 18 Tier 2, and 50 Tier 3 plants (Declaration Of Noxious Weeds accessed on Oct 2022). Only Tier 1 weeds must be eradicated without conditions. Of the knotweeds, only Japanese Knotweed (Fallopia japonica) is listed as a Tier 1 plant. Manitoba’s Water Protection Act (C.C.S.M. c. W65) prohibits possession of aquatic invasive species, including the most extensive list of invasive aquatic species of any province. 21 plants are on the current list (accessed Aug 18, 2023). This list is more precise regarding nomenclature. Tamarisk exclusions list:  Tamarisk ramosissima, T. chiniensis, T. parviflora or any cultivars, variety, or hybrids. Purple loosestrife lists Lythrum salicaria or any cultivars, variety, or hybrid. Both Myriophyllum aquaticum and M. spicatum are included.

Manitoba C.C.S.M. c. N110 The Noxious Weeds Act

THE WATER PROTECTION ACT (C.C.S.M. c. W65) Aquatic Invasive Species Regulation

Declaration Of Noxious Weeds In Manitoba

Controling Noxious Weeds

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

NB Provincial legislation

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

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:

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

NS Control Regulations (Reg. 57/68)
NS Fisheries and Coastal Resources Act
NS Weed Control Regulations:
List of weeds replaced: O.I.C. 2003-536, N.S. Reg. 219/2003.
Halifax Invasive Species on Watch List

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

A Risk Assessment of Invasive Alien Species in the NWT

Invasive alien species NWT Information Page

NT Brochure

Report on the 2016 Survey of Exotic Plants along Northwest Territories Highways

A Risk Assessment of Invasive Alien Species in the NWT S. Carrière


In NunavutThe 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)


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

New restricted species

Removal of Aquatic Invasive plants is permitted in accordance with rules explained here (This is not particularly clear).

Invasive Species Act, 2015, S.O. 2015, c. 22

Ontario Invasive Aquatic Plant List

Weed Control Act, RSO 1990, c W.5, <> retrieved on 2022-03-11

Conservation Authorities Support New Invasive Species Act (2015).

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 ).

PEI Weed Control Act


PEI Invasive Plant and Animal Species

PEI Invasive Plant Council


Agricultural Abuses Act (R.S.Q. c. A-2). “Mauvaises herbes et plantes envahissantes.” The Act was repealed in 2018. Please let us know what regulations impact invasive plants in that province.

Les mauvaise herbes agricoles:


SaskatchewanWeed 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 Aquatic Plants Nuisances

The Fisheries Regulations prohibit Saskatchewan residents and visitors from importing, possessing, transporting or selling aquatic invasive species. The list of aquatic species does not include plants.


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: