Florida’s state tree, the cabbage palm, has been standing strong and tall for centuries. But cabbage palms in areas of the state are dying, and experts believe that a type of bacteria called phytoplasma is to blame.
Researchers have identified affected cabbage palms in Hillsborough and Manatee Counties with symptoms that include a greater than normal amount of dead fronds in the lower canopy and death of the central leaf spear prior to the death of all other leaves.
Palm specialists believe that the decline in cabbage palms (known botanically as Sabal palmetto) is caused by the same phytoplasma that causes Texas Phoenix palm decline, a disease which has been confirmed in Sarasota, Pinellas, Hillsborough and Polk Counties.
The disease can be difficult to identify since over-trimmed palms and improperly fertilized palms in the landscape will show many symptoms that are similar but unrelated to this disease.
A new palm diagnostic key can help people determine what’s going on with potentially affected trees. Also watch for a new EDIS document called “Palm Problems: Field and Laboratory Diagnosis” (PP166) that will be released in August or September 2008.
If you think a palm might be affected, you can try an injection of oxytetracycline (OTC), which is known commercially as Tree Saver and has been known to help control phytoplasma diseases. The antibiotic is best injected by a professional arborist, typically three to four times per year. Resist the urge to cut down a tree just because it may become sick.
The strength of the cabbage palm has been legendary—the palm-trunk walls of Fort Sullivan in Charleston protected soldiers from cannon-fire during a British invasion in 1776. Now more than two hundred years later, researchers are searching for a way to help protect the palms.
Center for Landscape Conservation and Ecology
(352) 392-1831 x263