Weed Seeds Order Review Secondary Consultation Document
4.0 Comments on Feedback to Date

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  • Comments received in the first consultation demonstrated a dichotomy of views: the WSO role of both restricting the presence of a species because it is harmful, and permitting restricted amounts of a seed because it is difficult to remove from production fields or in processing, and therefore its presence in limited amounts should be allowed.
  • Stakeholder feedback emphasized the need for industry training on proposed species as well as the need for sample specimens.
  • Certain species were proposed for removal from the WSO because they are being considered as a crop type. Stakeholders supported these changes for two species, but there is lack of consensus for the removal of other species.
  • The demonstration of a species' ability to exhibit herbicide resistance was proposed as a consideration in determining the harmfulness of a species. There was some support for this concept, and more support for species demonstrating resistance to multiple modes of herbicide action. The CFIA continues to consider herbicide resistance one of the factors in listing weedy species.
  • Previous CFIA consultation documents contained information on frequency of species found in CFIA seed monitoring samples. This information is valuable to demonstrate movement of weedy species as contaminants of seed. However, these samples represent a small percentage of traded seed. Therefore, not finding a species in these samples does not indicate absence from Canada, and presence in samples does not indicate presence in Canada. Identification of a weedy species in monitoring samples does indicate seed is a pathway for this species. Presence in a large number of samples indicates that classifying a species in the WSO could result in significant quantities of seed being down graded.
  • The Canadian Seed Growers' Association (CSGA) declines pedigree status to seed crops containing Class 1 Prohibited Noxious weeds, not Class 2 Primary noxious weeds. The CSGA also declines pedigree status to seed fields of Canola, Mustard, Rapeseed and Oilseed Radish if they contain the weedy species cleavers or wild mustard.
  • Two species previously proposed for reclassification from Prohibited Noxious to Primary Noxious, Diffuse knapweed (Centaurea diffusa) and Spotted knapweed (Centaurea stoebe), are herein proposed to remain Prohibited Noxious, although they are present in Canada. The CFIA is continuing to propose the reclassification of Russian knapweed (Acroptilon repens) from Prohibited Noxious to Primary Noxious, as it is so widespread in Canada that it would fit best as a Primary Noxious weed. Official control programs exist for these species in one or more provinces or municipalities.

Species Listings

  • This secondary consultation document recommends moving forward with changes in species listing where there was consensus.
  • No changes from WSO 2005 are proposed to Classes 4 and 5, with the exception of the removal of Cirsium arvense (Canada Thistle), Elytrigia repens (couchgrass) and Sonchus arvensis (Perennial sow thistle) from Class 5. These three species were removed from Class 5 in order to eliminate duplication as they are listed in Class 2 which is now proposed to apply to all Grade Tables of Schedule I.
  • Stakeholder feedback on the regulation of weedy plant species under the Plant Protection Act may affect WSO listings of Prohibited Noxious species.

Requirements for Regular Changes to the WSO

  • Regular and predicable updates to the WSO are recommended. As additional plant species are added to List of Regulated Pests, updates to the WSO will be required.
  • Future revisions should consider fewer classes in the WSO.
  • Future revisions to the Grade Tables should consider higher standards for weed seed content.
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