MIAMI — A plant illness that could endanger Florida's $9 billion citrus industry has been found for the first time in the United States, agriculture officials said Friday.

The bacterial disease known as citrus greening was found in samples collected from two trees in South Florida, officials said.

Citrus greening is not a threat to humans but it has harmed trees in Asia, the Arabian Peninsula and Africa. Its first U.S. detection was confirmed by the U.S. Agriculture Department after state scientists sent the samples there.

The disease, primarily transmitted by insect, affects the vascular system of plants and causes infected trees to die in a few years.

"It would definitely be devastating to the citrus industry" if allowed to spread unchecked or if it's found to be widespread already, said Denise Feiber, spokeswoman for the Florida agriculture department.

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.

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.

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

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.

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

Source: Associated Press