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Ontario’s Ministry of Agriculture and Food (OMAF) is proposing an amendment to R.R.O. 1990, Regulation 1096 – General (the Regulation) in order to update the Schedule of Noxious Weeds.

This long overdue proposal would remove milkweed spp. (scientific name Asclepias spp.) from the Schedule of Noxious Weeds in the Regulation. Milkweed is an essential food for monarch butterflies, whose population has crashed in recent years. Removing milkweed from the Schedule will allow it to be planted widely, for example in gardens, on road verges, and railway and powerline rights of way, as conservation groups are encouraging people to do. This is a great project to do with children.

“Under the Weed Control Act, R.S.O. 1990, c. W.5 (the Act), every person in possession of land is obligated to destroy all noxious weeds on it. However, this duty does not apply to noxious weeds or weed seeds that are far enough away from any land used for agricultural or horticultural purposes that the weeds or weed seeds do not interfere with that use. As a result, any person in possession of land where prescribed noxious weeds are present, and which could negatively affect lands used for agricultural or horticultural purposes, is responsible for controlling any prescribed noxious weeds present on it. Under the Act, the person in possession of the land may also be held responsible for the costs associated with removal. Depending on the lands and the conditions of use, this responsibility could rest with landowners (including farmers), municipalities and conservation authorities, among others.

The Schedule of Noxious Weeds lists milkweed spp. as the common name of the weed and Asclepias spp. as the scientific name of the weed. This description is very broad. As written, the term could extend to all species in the Asclepias genus, which includes many individual species, including four-leaved milkweed (a species at risk in Ontario) and other species in the Asclepias genus that are not considered a threat to agriculture or horticulture in Ontario.

The species common milkweed (Asclepias syriaca) has traditionally been viewed as a noxious weed in Ontario. It is considered to be common to widespread in many parts of southern and northern Ontario and it forms an important part of the native and naturalized vegetation in the province. Common milkweed also provides an important habitat and a larval food source for the Monarch butterfly. Milkweed species also play a key role in biodiversity in Ontario. The presence of common milkweed on lands that are not being actively farmed would be considered a low to negligible risk to activities on nearby agricultural or horticultural lands. Farmers can take proper management steps on their own lands to reduce the threat that common milkweed can pose to grazing livestock. Since milkweed spp. was added to the Schedule of Noxious Weeds initially, there has been an expansion in the number of management options available to farmers to address common milkweed on lands that are actively farmed.”

In addition, the List will now prohibit dog-strangling vine:

“Dog-strangling vine occurs in several places in southern Ontario, growing in ravines, hillsides, waste areas, fence lines and hedges. It forms dense patches and can overwhelm other vegetation, including agricultural crops. It is an invasive plant that can be difficult to control once established. Although the Monarch butterfly is attracted to the plant, any eggs laid will not survive. It is, therefore, considered a hazard to Monarch butterfly populations.

The proposed changes would support important government initiatives related to biodiversity and the environment, such as the commitments made in Biodiversity: It’s in Our Nature, Ontario Government Plan to Conserve Biodiversity, 2012–2020, the government’s response to the Biodiversity Strategy. At the same time, the proposed regulation would remove the legal burden on persons in possession of land to remove common milkweed where its presence could negatively affect lands used for agricultural or horticultural purposes. The addition of dog-strangling vine will provide more tools to local weed inspectors to address this invasive plant species.” Public Consultation:

This proposal has been posted for a 45 day public review and comment period starting February 28, 2014. If you have any questions, or would like to submit your comments, please do so by April 14, 2014.

EBR Registry Number: 012-1204: Updating the Schedule of Noxious Weeds in R.R.O. 1990, Regulation 1096 – General, made under the Weed Control Act, R.S.O. 1990, c. W.5 (removal of milkweed and addition of dog-strangling vine)

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