With the growing season underway, many residents are returning to gardens, pastures, and outdoor spaces. This is an important time to be aware of recent updates to Alberta’s Weed Control Regulation under the Weed Control Act. The Government of Alberta has revised the Regulation to strengthen our defense against invasive species and better protect our environment and agriculture.
Why are These Species Regulated?
Invasive plants can devastate native ecosystems, choke out agricultural crops, and even damage local infrastructure. Weed regulations aren't just a list of "bad plants”, they are a strategic tool. Regulation is most effective early in an invasion, when a species can still be contained or eradicated.
To ensure our efforts are focused where they have the greatest impact, the Weed Control Regulation classifies these plant threats into two main categories:
- Prohibited Noxious: These are plant species that are either not yet present in Alberta or are found only in small, localized areas. Because they pose a massive threat, early detection is critical, and they must be completely destroyed when found.
- Noxious: These plant species are already established in parts of Alberta. To prevent their further spread they must be controlled, as they severely impact our native biodiversity and agricultural production.
What Has Changed?
The most significant update is the revision of the list of regulated plants under the Weed Control Regulation. Several new species have been added, and a number of existing species have been reclassified to better reflect their current distribution and management needs across Alberta.
Some species have been added as prohibited noxious, meaning they are either not yet established in Alberta or are only found in very limited, localized areas. These are high-priority species where Early Detection and Rapid Response (EDRR) is critical to prevent establishment.
Other species have been added as noxious, reflecting plants that are already present in the province but require control to prevent further spread and reduce impacts on agriculture and natural ecosystems.
In addition, several species have been reclassified from prohibited noxious to noxious. This shift reflects the reality that these plants are now more widely established than previously known, making eradication no longer feasible and shifting management focus toward long-term control.
A full list of added and reclassified species is provided in the graphic below.
Tools to Help Identify and Manage
If you aren't sure what these newly listed weeds look like, we've got you covered.
- The Alberta Invasive Species Council provides detailed invasive plants factsheets with identification and management information.
- The updated 5th edition of Invasive Plants of Alberta is also available, with digital access online and printed copies through the AISC store later this summer.
Dig Deeper
Learn more about the new regulations with a free webinar hosted by the Alberta Invasive Species Council and Alberta Agriculture and Irrigation.
Webinar Details:
- Title: Invasive Plants in Alberta - Understanding the New Weed Regulations
- Date: June 3, 2026 at 6:30 p.m.
- Registration is available here.
Note: this webinar will be recorded and available on AISC's YouTube channel after the event.