Citrus Canker

MONTGOMERY, Ala.– Citrus canker, a federal and state regulated plant disease, was detected in Baldwin County, Ala. in June of 2021. As required by federal law, the Alabama Department of Agriculture and Industries (ADAI) established a citrus canker quarantine for Baldwin County on February 9, 2022.

Citrus Canker is caused by a bacterial pathogen (Xanthomonas axonopodis citri) and affects all citrus species. This was the first detection of citrus canker in our state despite biannual surveys conducted by ADAI plant inspection staff.

While not harmful to humans, citrus canker significantly affects the vitality of citrus trees, causing leaves and fruit to drop prematurely. A fruit infected with canker is safe to eat but has reduced marketability as fresh fruit. The bacteria can remain viable on plant surfaces for several months. Canker lesions expel bacterial cells, which can be dispersed by wind and rain. Infection may spread further by heavy rain and wind events, such as hurricanes.

People can move the disease by moving contaminated equipment and tools, tree clippings, untreated infected fruit and infected plants. The disease thrives in areas with high rainfall and high temperatures. Citrus species vary in their susceptibility to citrus canker, with grapefruit and limes being the most susceptible.

ADAI and USDA APHIS Plant Protection and Quarantine (PPQ) officials will be conducting a delimiting survey beginning in late spring to determine the extent that the pathogen may have spread. Outreach and education to nurseries, plant dealers and homeowners will be conducted concerning citrus canker as well.

For more information about citrus canker or the citrus canker quarantine, please contact Christel Stewart by email at or by phone at 334-240-7225.