APHIS deregulates chrysanthemum white rust

The U.S. Department of Agriculture’s Animal and Plant Health Inspection Service is deregulating chrysanthemum white rust, a fungal disease caused by Puccinia horiana, and removing its designation as a quarantine pest.

An APHIS economic evaluation concluded that the current eradication-based approach is no longer technically or economically justified. CWR is now considered established in the United States, and growers can manage it more effectively using commonly available fungicides and other industry practices, APHIS said.

After extensive analysis and research, APHIS has determined that Chrysanthemum spp., Leucanthemella serotina and Nipponanthemum nipponicum may be safely imported into the continental United States as cuttings and in vitro plantlets from 20 countries — including Belgium, Bolivia, Brazil, Colombia, Costa Rica, El Salvador, Ethiopia, Germany, Guatemala, Kenya, Mexico, the Netherlands, Nicaragua, Panama, Spain, Tanzania, Tunisia, Uganda, the United Kingdom and Vietnam — under a systems approach.

APHIS also authorizes the importation of Chrysanthemum spp., Leucanthemella serotina and Nipponanthemum nipponicum cuttings, in vitro plantlets and plants with roots from Canada under a separate protocol.

APHIS is removing CWR-specific import restrictions on fresh-cut flowers and consolidating all commodity-specific import requirements into the Agricultural Commodity Import Requirements database. In addition, APHIS is adding the notice-based process to 7 CFR 319 Subpart P-Cut Flowers to enable a more rapid response to changing pest situations on this commodity.

To view the details of this action, go to regulations.gov and enter APHIS-2021-0081 in the search field for the plants for planting regulation and APHIS-2019-0024 in the search field for the chrysanthemum fresh cut flowers rule in the Federal Register.

These changes are effective 30 days after publication in the Federal Register on Nov. 9, 2026.

AmericanHort is hosting a webinar with USDA APHIS examining what this regulatory change means for growers, propagators, importers and the broader horticulture industry. It takes place Tuesday, Nov. 3 from 3 to 4 p.m. Eastern Time.

Representatives from USDA APHIS's Plants for Planting Policy team will provide an overview of the deregulation decision, explain the new systems approach for importing chrysanthemum cuttings and in vitro plantlets from approved countries, and discuss implementation requirements and next steps.

The webinar, which is free for AmericanHort members, will also include an opportunity for attendees to ask questions directly to USDA APHIS representatives.