Guest Blog - Reducing the sales of invasive plant species in Canada – to safeguard biodiversity

By: Canadian Coalition for Invasive Plant Regulation 


This Invasive Species Awareness Week, we bring you a guest blog by the Canadian Coalition for Invasive Plant Regulation (CCIPR).


Invasive species management is an important part of native species restoration, if the landscape is dominated by aggressive invaders, all the native plants we restore will be drowned out! CCIPR works to stop invasive plants at the source, by stopping sales of the worst culprits in plant nurseries for the horticultural trade.


Read more below and on their website,



The global trade in ornamental nursery stock is the primary pathway for the introduction of nonindigenous invasive plants in Canada. Those invasive plants can threaten biodiversity and diminish its associated ecological, economic, social, cultural, and intrinsic values. 


To protect our economy, environment and public health from invasive plant species, Canada needs to:

  • Improve policies and legislation.  
  • Establish a permanent national body with responsibility for nonindigenous invasive species.  
  • Create a science-based national plant risk assessment database. This database would provide the name(s) and description of each nonindigenous plant sold in Canada along with its regional ranking as a high, medium, low, or an insignificant invasion risk.   
  • Require that all imports of plants new to Canada undergo risk assessments. 
  • Ban the sale and movement of high-risk invasive plant species, where regionally appropriate.  
  • Require labelling to identify and educate the public about lower-risk invasive plants.  
  • Provide continued and stable funding for public education.   
  • Incentivize the adoption of the National Voluntary Code of Conduct for the Ornamental Horticultural Industry.    

The number of invasive plant species in Canada is steadily growing. With that growth, the management costs and  environmental damage rise. Canada needs to act now to reduce the potential damages and the price tag for management and mitigation.  


At the federal level, invasive plant prevention focuses on safeguarding Canada’s food supply–the plants and animals in the agricultural sector. While laudable and necessary, current regulations fail to safeguard our natural flora and fauna. Canada needs to develop new federal regulatory tools. Canada needs legislation similar to the European Union (EU) act for the prevention and management of the introduction and spread of invasive alien species (1143/2014). This act aims to minimize the adverse effects of invasive species on biodiversity and related ecosystem services, as well as human health and safety. In addition, Canada could pass legislation requiring a risk assessment paid for by importers, before any plants not yet present are introduced, as is required by Australia’s Quarantine Proclamation (1998). Only with the proper legal underpinnings can Canada restrict the trade of highly invasive ornamental plants.  

To comply with international conventions and agreements, any trade restrictions must be based on sound scientific risk assessments. Therefore, in addition to enhancing its regulatory framework, Canada needs to improve its scientific capacity and develop a robust national database.  An impact ranking system like I- Rank should be used to categorize invasive plants as High, Medium, Low, or Insignificant risks to biodiversity.

A national database would ensure that reliable information is available to support the activities of federal and regional governments, Indigenous communities, and non-governmental organizations. A permanent federal body dedicated to nonindigenous invasive species is needed to clarify ‘who-does-what’ and coordinate interdepartmental and inter-agency cooperation at both the federal and provincial/territorial levels. 

Education and public awareness are necessary for the successful prevention and management of invasive plants. This means all levels of government should provide ongoing and stable funding for programs that raise awareness, build knowledge and skills, and change attitudes and behaviours. An informed public is more likely to support and promote the control of invasive plants.   

To this end, consumers deserve clear, consistent labelling that tells them what they need to know when shopping for plants. For those lower-risk invasive plants, sellers should be required to:    

  • Inform consumers the plant poses potential risks to the environment,
  • Provide recommendations for alternative noninvasive plant choices, and     
  • Describe measures necessary to reduce the risk of spread.   

Informed consumers are more likely to understand the risks posed by invasive plants and reduce their spread.

An effective strategy for the prevention and management of invasive plants will require a combination of legally binding and voluntary approaches. Sustainable forest management standards have been successful in promoting comprehensive environmental and social standards in the forestry sector. Similarly, the ornamental horticultural sector should be encouraged to comply with legislation and reduce the numbers of invasive plants sold in Canada. While there may be short term losses in a small segment of the sector, there will also be opportunities to strengthen the sector and develop a “greener” industry that capitalizes on regional botanical uniqueness. 

Reducing the sale of invasive plant species in Canada and protecting Canada’s biodiversity will require a multi-faceted approach. Improving legislation and oversight, building a knowledge base, providing education and consumer awareness programs together can form the basis of a successful strategy. By following this strategy, Canada can help to safeguard nature, which is essential for human health and well-being, economic prosperity, food safety and security.


Learn more, here:

Don't Plant That, Plant This!

Written by: Summer Graham



With 2021-2030 being the UN decade on ecosystem restoration,

I think it is a good time to reflect on the importance of healthy, functioning ecosystems as well as take action in restoring them. Some organizations have spearheaded restoration efforts like the Bonn Challenge, which aims to restore 350 million hectares of degraded ecosystems by 2030! While these large-scale targets are inspiring, you may be wondering if there is anything you can possibly do to help. Well there is - and it starts in your own backyard!


Some common garden species became popular and widespread before they were known to be invasive outside of their native range. By replacing these problem species with native ones, you can reduce the risk of contributing to the degradation of near-by native areas. You may think “This Common Buckthorn is just in my backyard, it doesn’t matter if it’s planted here” but Buckthorn berries are often eaten by birds, which then spread seeds all over! 


Many invasive, non-native garden species are unfortunately still sold in garden centres, so informing yourself (and your friends!) on which species to avoid buying is the first step. Then, you can determine which native species would be most ideal for your garden. By using the Ontario Invasive Plant Council (OIPC) Grow me instead guide, gardeners in Ontario can easily swap invasive species with native ones! See below for some recommended replacements to common Southern Ontario species:


                         Instead of Planting....                                                                                  ...Plant This! 



(Vinca minor)


View Plant


Wild Geranium

(Geranium maculatum


View Plant


European Lily

of the Valley

(Convallaria majalis)


View Plant



Starry False Solomon's Seal

(Maianthemum steallatum)


View Plant



(Aegopodium podagraria)


View Plant



Large-leaved Aster

(Eurybia macrophylla)


View Plant


English Ivy

(Hedera helix


View Plant



Wild Strawberry 

(Fragaria virginiana


View Plant



Yellow Arch-angel

(Lamiastrum galeobdolon)


View Plant



Zig-zag Goldenrod

(Solidago flexicaulis)


View Plant



Similar resources are available for Alberta, Yukon, BC, Saskatchewan, and Manitoba (see below). Now that you are inspired to replace your garden with some native species, head to our native nursery locator to find some native plants near you!


Additional Resources:

OIPC Grow Me Instead Guides Southern Ontario

OICP Grow Me Instead Northern

Alberta Grow Me Instead 

Yukon Grow Me Instead 

Be Plant Wise BC 

Saskatchewan Invasive Species Council

Manitoba Grow me Instead



Tips and Tricks for Invasive Species Management

Written by: Summer Graham 


Management of invasive species is a topic that often comes up when discussing natural environments and native plants. Maybe you are looking to restore an area, but Garlic Mustard (Alliaria petiolata) currently dominates the site. Or, maybe you want to convert your garden into a native plant sanctuary, but already established non-native species like Periwinkle (Vinca minor) and Goutweed (Aegopodium podagraria) are giving you a hard time.


GoutweedLuckily, there are a variety of techniques that can be used to tackle these invaders, clearing the way for native species to once again thrive. Please note that effective strategies, timing, and appropriate disposal varies for different invasive species, so be sure to check the best management practices for the species you are trying to manage. In this blog, we cover some of the most common methods for tackling invasive species. Take a look to get some ideas, and then refer to the resources below for some species-specific best management practices!



Management Techniques - 


Prevention/early detection-

Prevention and early detection is the most effective and economic way of controlling invasive species. This method involves managing an area to prevent the introduction and establishment of invasive species. Prevention might include asking hikers to clean off their boots at a trail head, to prevent any non-native seed from being introduced to a natural area. Early detection and rapid response (EDRR) is the next best option, with some organizations using citizen science like EDDMaps to help with early detection of invasive species.

Pros: stops infestations before they begin; often the most economical option

Cons: requires ongoing monitoring and planning to prevent introduction/establishment of invasives



This method uses mowing or cutting of an invasive plant to limit seed Periwinkleproduction and spread. This method needs to be repeated a couple times a year, and timing varies by plant. Overall, this can be less labour-intensive than other methods while still achieving desired results.

Pros: reduces seed production; relatively easy if accessible by mower

Cons: restricted by timing windows; won’t always kill plants but will reduce spread through seed


Cultural/ Competition-

Includes re-vegetating and promoting establishment of a healthy ground or crop cover to help hold off invasive species. Helps to establish native plant communities, which is ideal for projects that aim to not only remove invasive species, but also restore native habitat.

Pros: long term management; good for environmentally sensitive areas; introduces native plants to the site

Cons: site and soil can be unfavourable; can be labour-intensive and costly



Works well with single plants and small infestations, and populations can often be removed completely (rather than just managed/reduced in the long term). This method involves manually pulling plants out (when soil is loose and moist) repeatedly and removal from the site. Works well for species such as Garlic Mustard if repeated annually before plants flower and seed.  You can also dig out the plant (including roots) to remove them from the site.

Pros: can be used in sensitive areas; can manage small patches or single plants; persistent pulling can manage perennials

Cons: can be labour and time intensive; limited to small populations; many invasives reproduce through rhizomes which are hard to remove; specific timing window for removal due to seeds; must be done repeatedly



Biological control involves the introduction of a predator (often an insect) to control the invasive species by attacking or feeding on it. Invasive species are often considered invasive due to the fact that they were introduced to an area without their natural predators to keep them in check, this method aims to restore the natural balance between species.

Pros: uses natural predators for control; good for environmentally sensitive areas

Cons: slow progress; takes many years to develop and test biological control species; doesn’t “eradicate” the species; aren’t available or approved for most prevalent invasives; introduced control species can also become problematic in an ecosystem



Note: only certified and licensed individuals should undertake spraying of pesticides to control invasive species. All provincial and federal laws, pesticide regulations, and pesticide best management practices and safety protocols should be followed.

Chemical treatment involves spraying of pesticides and herbicides to control invasive species populations. This can often be effective in combination with other methods such as cutting and mowing, to reduce the amount of chemical needed.

Pros: often effective; can be targeted to certain plants/types of plants (e.g. herbaceous vs. woody); less labour than mechanical/manual methods

Cons: precautions need to be taken to limit the effects on surrounding non-target plants; limited use in sensitive environments; concern from public/community groups



Canadian Council on Invasive Species

Ontario Invasive Plant Council (ON)

OIPC Best Management Practices

Yukon Invasive Species Council (YT)

Coastal Invasive Species Committee (BC)

Alberta Invasive Species Council (AB)

PEI Invasive Species Council (PEI)

New Brunswick Council of Invasive Species (NB)

Invasive Plant Species Identification Guide (SK)

Invasive Species Council of Manitoba (MB)



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