US: Citrus greening confirmed in South Florida plants

The U.S. Agriculture Department confirmed Friday the first U.S. detection of a plant illness known as citrus greening from samples collected from two trees in South Florida.

The bacterial disease, which is primarily transmitted by an insect, is not a threat to humans but poses a potential danger to Florida's $9 billion citrus industry, which already has battled another damaging disease, citrus canker, officials said.

Citrus greening has harmed citrus in Asia, the Arabian Peninsula and Africa. Its first U.S. detection was confirmed by the U.S. Agriculture Department's Animal and Plant Health Detection Service after state scientists sent samples there, according to the Florida Agriculture Department.

The disease affects the vascular system of plants and causes infected trees to die in a few years, officials said.

"It would definitely be devastating to the citrus industry" if allowed to spread unchecked or if it's already found to be widespread, Florida agriculture department spokeswoman Denise Feiber told The Associated Press. "It has proven to be devastating in other countries."

The Asian version of citrus greening was found on two samples of pummelo tree leaf and fruit samples 14 miles apart in the city of Homestead, a farming center in Miami-Dade County. Scientists and agriculture officials were investigating whether the illness had spread beyond that area, officials said.

"There are just so many unknowns right now because it's a new disease in the United States," Feiber said.

The disease probably arrived in Florida from infected Asian plant material that came into contact with the insects that spread it, known as citrus psyllids, Feiber said.

"In a sentinel state with so many ports, it makes the task of protecting the plant life a lot more difficult," she said.

Feiber said agriculture officials had been testing for the disease since the insects that carry it were found in Delray Beach in June 1998.

Officials said they had been monitoring the situation since then and credited their vigilance with what they called on a news release "early detection of the disease." If the disease is found early, eradication may be possible, the news release said.

Because there is no cure, trees found to have been infected will be destroyed as federal and state scientists determine how far citrus greening has spread.

But the disease is not airborne, so finding and killing carrier insects is critical, Feiber said.

"There are ways to manage it if you manage the insect and remove the infected trees," she said.

The citrus greening threat is just another headache for Florida agriculture officials and citrus growers - and potentially homeowners - who have dealt with citrus canker for about a decade.

Canker, also caused by bacteria and spread by the wind, can affect all citrus varieties, including grapefruit, oranges and tangerines. Infected trees develop small brown lesions on leaves, stems and fruit. The canker eventually reduces tree productivity, but is not dangerous to people.

The state has destroyed about 2.5 million trees in commercial groves and 650,000 trees in residential areas in an attempt to get rid of it.

In the case of citrus greening, Feiber said it was to early to tell if exposed trees - not just the infected ones - would need to be cut down, and if homeowners would be affected. Under its canker eradication program, the state removes trees within 1,900 feet of an infected one, a policy that spawned legal challenges from homeowners.

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