Move over citrus canker

The newest threat to citrus trees here in Florida is something called citrus greening. A bacterial disease carried by an Asian insect. This was reported in a front page article in today's Sun-Sentinel.

Citrus is big business in Florida. Another eradication program will certainly be done, how much it will cost taxpayers is yet to be determined.

Open Post- Basil's Blog

A deadly new citrus disease is spreading through southeast Florida, creating a fresh threat to the citrus industry and raising the possibility of another costly and disruptive eradication program.

Citrus greening, a bacterial disease carried by an Asian insect, stunts growth, leads to bitter, misshapen oranges and grapefruits, and eventually kills the tree. Agriculture officials and growers say the disease could pose a greater threat than citrus canker, still widespread despite a $500 million campaign to eradicate it.

State and federal inspectors have found citrus greening on at least 160 trees in Miami-Dade, Broward and Palm Beach counties, and they're looking for evidence of the disease farther north.

"This is as bad as it gets," said Nathaniel Roberts, general manager of the 4,000-acre Callery-Judge Grove in western Palm Beach County. "You better act very aggressively and very strongly. If you want to preserve the citrus industry in the state of Florida, you need to stop this thing before it spreads."

Agriculture officials and scientists will meet Friday at the Citrus Research Education Center in Lake Alfred to plan how to study and control the disease, which has never before appeared in the United States.

Richard Miranda, spokesman for the Florida Department of Agriculture, said there is no cure for citrus greening; infected trees must be cut down. Among the options to stop its spread is the use of pesticides, which he said would be applied only on commercial groves, never in residential areas.

Any proposal to fight citrus greening is certain to take into account the bitter fighting over the citrus canker eradication program, where homeowners filed lawsuits, packed public meetings and unleashed dogs to prevent chain-saw crews from taking their trees. The opposition tied up the eradication program in court for years.

Helen Ackerman, a Plantation homeowner who has been active in the opposition to the canker eradication program, said the state and federal agriculture agencies should take the opportunity to avoid the mistakes of the past -- although she said it appears they're already stumbling.

"Where's the conference where everybody's invited at the local level to discuss it?" she asked. "I'd like to know all the biology on the control of this little bug. When you discovered this insect, what action did you take to eliminate the insect? What's your plan? Who did you consult?"

Agriculture officials began to worry about citrus greening in 1998, when the insect that carries the disease was found in Delray Beach. Inspectors surveyed citrus trees but didn't discover the first case of citrus greening until last August.

Known as "yellow dragon disease" in China, where it may have originated, citrus greening is found throughout east Asia and in some major citrus-growing countries, including Florida's arch-rival, Brazil. The disease attacks the vascular system of plants, leading to mottled leaves, severe fruit drop, aborted seeds and underdeveloped, lopsided, bitter fruit.

"Citrus greening is a very destructive disease," states a report in Florida Entomologist by Susan Halbert, a state insect expert who discovered the disease in Florida, and Keremane Manjunath. A study on Reunion Island in the Indian Ocean, where citrus greening is widespread, found that 65 percent of trees were badly damaged within seven years of planting. The report quoted a study that found citrus greening had caused a "marked decline" in the citrus industries of Saudi Arabia and India.

The bacteria are spread by the Asian citrus psyllid, an insect about a quarter-inch long. The report states the insect can fly several kilometers, indicating the disease can quickly spread long distances. Fighting the disease by cutting down trees within its range "is likely to provoke extreme public outcry," the report notes.

So far, inspection teams have been surveying trees and cutting them down only with the permission of homeowners, Miranda said. Once the disease is confirmed, the teams go to the homeowner for permission to cut down the tree. About 80 percent of homeowners have agreed, Miranda said. So far, 12 trees have been cut down. He said agriculture officials wanted to cut them down faster but have been hampered by weather and the need to find a contractor.