New Palm Disease in Florida

Two types of palms in Florida — the Canary Island date palm and the Sabal palm (shown here) — have the new disease. They suspect that plant-hopping insects feeding on the trees’ nutrient-carrying tissue carry the phytoplasma. Photo Courtesy of Central Florida Palm & Cycad Society (website)

“It’s a new disease, and there are no easy answers,” said Hillsborough County forest extension agent Rob Northrop.

They do know, however, the tall, slender trees that are the source of “swamp cabbage” — the edible hearts of palm — are turning brown and dying.

The disease has been confirmed in sabal palms along Brandon Parkway, in Ruskin’s E.G. Simmons Park and along U.S. 41 south of the Alafia River, Northrop said. It was found in Manatee County two weeks ago.

It’s hard to determine how widespread the disease is because there are no field tests, and it can’t be diagnosed by simply looking at the trees, Northrop said. Confirming the disease requires expensive DNA testing. However, the disease is probably caused by the same phytoplasma — a bacterium without a cell wall — that’s killing four other palm species: the Canary Island date palm, the edible date palm, the wild date palm and the queen palm, UF researchers said.

Because each tree can cost thousands of dollars, Northrop suggests that people stop planting palms until more is known about the disease. For now, homeowners who find withering palms in their yard should not immediately remove the tree, Northrop said. Instead, disinfect pruning shears between trimming each palm and consider hiring an arborist to inject an antibiotic. The antibiotic, called TreeSaver, is inexpensive, but Northrop suggests hiring an arborist to inject it correctly. That could cost a couple hundred dollars and should be done three to four times a year.

The antibiotic isn’t practical on a large scale, said Monica Elliott, a UF plant pathology professor based in Fort Lauderdale, so there’s no real solution yet for stopping the disease.

Source: JESSICA VANDER VELDE, St. Petersburg Times