The White Lists
(Canada and U.S.)

There are two separate initiatives to create "white lists" of plants deemed to be acceptable in North America. Any plants not specifically listed on these "white lists" will be restricted or prohibited in some way. The trouble is that more than 90% of plant species known to man are not on the one "white list" that we have seen so far, and we worry that the other list will be even more restrictive. This means that the movement of plants across the Canada-U.S. border will be affected, and most species of seeds will be restricted entry into Canada.

In March we learned about a proposal by the Canadian Food Inspection Agency (CFIA) to implement an invasive plant policy for Canada. We believe the policy goes much too far and we are deeply concerned that it will infringe on the rights gardeners and herbalists to grow plants in Canada. We have a separate Issues page on this policy which can be accessed here.

Earlier we learned about the proposal by U.S. and Canadian governments to introduce a "white list" of plants that will limit the entry of live plants into each country under a vitally important joint Canada-USA greenhouse certification program. The United States Department of Agriculture (USDA) and the CFIA solicited comments from stakeholders last fall on the proposal to replace the current list of prohibited plants with a new list of allowed plants. What this means is that if a plant is not on the allowed list it cannot enter the U.S. from Canada or vice versa. Many thousands of plants including many herbs will be barred entry under the proposal.

This change is highly significant for both countries because it appears to be part of a larger attempt to implement the controversal "white list" approach to the control of cross-border plant and seed movement. The proposed "white list" is far more restrictive than the current "black list" of prohibited plants that has been in place since 1996. The new "white list" includes less than 1000 plant genera, out of over 12,600 genera of flowering plants known to man. This means that more than 11,600 genera of plants representing over 90% of all plants will be banned under the program. Compare this to the current "black list" that bans less than 100 genera.

Some suggest that the powerful anti-invasives movement in the U.S. is behind the push to introduce "white lists" of plants that are allowed into the country. While invasives are a problem for both countries, the new list will affect thousands of plants already in the horticultural trade, and will limit the introduction of new plants to gardeners.

For gardeners, it is worth reflecting on how many new plants that you have enjoyed growing over the past 10-20 years, and how many of them might not have been available to you had this "white list" been in place.

During the comments period we encouraged gardeners, herbalists, commercial growers, and the gardening and herbal media to submit comments to both the CFIA and the USDA. The official comments period is now closed and so far we have no indication from either the CFIA or the USDA whether any of our suggestions and concerns have been taken into consideration.

The comments period ended October 31, 2010.

Michael D. Ward, Senior Accreditation Projects Manager, USDA-APHIS-PPQ ( was responsible for receiving comments from U.S. stakeholders. Canadian stakeholders submitted comments to the CFIA’s horticulture unit (

The relevant documents affecting the binational Greenhouse Certification Program, including the proposed lists of authorized genera and families, are posted here.

Our comments to the proposal can be found here and here. The list of Richters plants that are not on the proposed "white list" is posted here. These plants will be prohibited entry under this proposed new policy for the Greenhouse Certification Program.

[Updated Apr. 15, 2011]

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