Citrus Canker

Contagious Canker Threatens Florida's Citrus Industry
Washington Post, March 20, 2000

MIAMI ­ In back yards all over this lush-green city, orange trees have had to be chopped down and burned. South of here, in Florida City and Homestead, about half of the $20 million lime crop has been lost. And now, the heart of the state's $8.5 billion citrus industry, in central Florida, is beginning to feel the threat as a highly contagious bacterial disease with no known cure keeps moving north. The disease is called citrus canker; it is so dreaded that state and federal officials have just allotted $175 million to battle it and assigned nearly a thousand workers to the fight in Dade and Broward counties alone. "Suffice it to say that if left unchecked, this would wipe out the citrus industry," said state agriculture department spokesman Terence McElroy. "It is a huge threat. It is arguably the most devastating citrus disease a citrus region can have." Citrus canker does not affect humans, but it can ruin an orange, lime or grapefruit grove. Although often not visible for several years, it weakens the trees, eventually leaving them unproductive. In later stages, it is characterized by the unsightly brown splotches that cover the fruit and leaves. "It kind of looks like the fruit has acne, like a kid took a brown magic marker and drew polka dots," McElroy said.

Florida's multibillion-dollar citrus crop is the biggest component of the state's agricultural industry, which is second only to tourism in economic importance. The state produces 75 percent of the nation's citrus fruits, and worldwide, is second only to Brazil in citrus production. About 140,000 workers are employed in the Florida citrus industry. This is the third canker outbreak in South Florida in the past 100 years and the most serious. The latest strain came from Asia and was introduced in October 1995 into a backyard garden in Miami, located within a half-mile of Miami International Airport, McElroy said. The disease is spread easily through wind and rain--and through the contaminated tools and equipment used by lawn-care workers. Already, the state has had to cut down 500,000 citrus trees in the Miami and Fort Lauderdale areas, which is far south of the main growing region. About 300,000 of the destroyed trees were in residential neighborhoods and the remaining 200,000 in lime groves. As many as 1.5 million additional trees in the area also need to be cut, McElroy said. "The thing is so contagious that scientists now tell us, if a tree is positively identified as having citrus canker, you must also cut down any other citrus tree within 1,900 feet - more than 600 yards in every direction," he said.

Central Florida citrus growers, who have been nervously charting the disease's movement northward, were dismayed recently to learn that the disease has penetrated the county north of Broward, Palm Beach County. Only a handful of residential trees in Boca Raton, in the southern portion of the county, have been infected, but that is enough to raise the alarm. "It's become a crisis," said Wendy Bourland of the Florida Citrus Mutual, the state's largest citrus organization with about 12,000 growers. "We have a weekly newsletter we publish to our members, and that's all we've talked about for months now." Growers throughout the state have been advised to limit access into and out of their groves, to be mindful of contaminated equipment and to haul fruit only in covered trailers, she said. "It's going to take everything we can to fight this disease," Bourland said. "You can't make it go away once it's arrived except to pull up the trees and burn them."