The U.S. Department of Agriculture Animal and Plant Health Inspection Service (APHIS) has announced an interim rule to allow the interstate movement of regulated nursery stock under certain conditions from areas quarantined for citrus canker, citrus greening, and/or the Asian citrus psyllid (ACP) to any area within the U.S.

Previously, interstate movement had been prohibited or restricted depending on the quarantine area.

“This rule will provide much needed economic relief for citrus-producing nursery growers in the quarantine areas,” said APHIS Administrator Gregory Parham. “Most of these nurseries are small businesses that have been impacted by the previous quarantine measures which were necessary in the short term to limit the spread of these devastating citrus diseases. To allow this new movement out of the quarantine areas, the rule establishes rigorous, science based safeguarding measures that will protect all citrus-producing states.”

With the interim rule, regulated nursery stock accompanied by a certificate can move interstate from areas quarantined for citrus canker, citrus greening, and/or the ACP to any U.S. area.

The interim rule also revises the regulations regarding the movement of regulated nursery stock under a limited permit from an area quarantined for the Asian citrus psyllid but not for citrus greening.

The rule defines citrus nursery stock as all plants for planting in the family Rutaceae including citrus and citrus relatives.

Certificates and limited permits will only be issued for shipments of plants originating from facilities that operate under a compliance agreement with APHIS, meet strict standards for the production of disease-free plant material, and employ safeguards during packing and movement.

The specific protocols for these agreements are outlined in an online document at

APHIS developed the protocols after conducting a comprehensive risk management analysis that examined citrus nursery stock as a pathway for the introduction of citrus canker, citrus greening, and the ACP from areas quarantined for any of these pests into any area of the United States.

The protocols include: labeling which facilitates traceability, recordkeeping, inspection, horticultural and sanitation practices, access to the facility by inspectors, surveillance, treatments, and facility requirements to safeguard nursery stock from citrus canker, citrus greening, and the ACP.

The movement of citrus nursery stock remains restricted in areas quarantined for sweet orange scab and citrus black spot.

Nursery stock from areas quarantined for sweet orange scab may move to non-citrus producing states under certain conditions. The entire states of Arizona, Florida, Louisiana, Mississippi, and Texas are quarantined for sweet orange scab.

Citrus greening, also known as Huanglongbing disease, is one of the most devastating diseases of citrus worldwide. While it does not pose a human health risk, it greatly reduces fruit production and causes economic losses.

Once infected, there is no known cure for a tree with citrus greening. A gnat-sized insect, the ACP spreads the bacterium that causes citrus greening as it feeds. The pest’s feeding activity can also seriously damage the citrus plants directly, especially new shoots.