ORANGE COVE, California (AP) -- Tom Mulholland is girding for battle against a tiny enemy that could devastate the orange grove he has spent his life cultivating. His adversary: the Asian citrus psyllid, a fruit-fly-sized insect with red eyes and a long, leaf-penetrating beak.
The psyllid, which can carry an incurable disease fatal to citrus trees, was spotted in August in Los Angeles, closer than ever before to the ribbon of central California where the state's $1.6 billion citrus-growing industry is concentrated.
California growers and agricultural officials are worried the state's citrus industry will be crippled by the disease carried by the psyllid, which devastated Florida's crops. The two states produced about 97 percent of the nation's 12 million tons of citrus during the fiscal year ending in June.
The feared infestation has prompted Mulholland and other citrus-belt farmers to put screens around their young seedlings, vigorously inspect their mature trees and tax themselves to fund research to stop the psyllid.
"It's like a war," Mulholland said in his tidy office set amid about 400 acres (160 hectares) of radiantly healthy Clementine and Satsuma trees on his farm around 200 miles (320 kilometers) north of Los Angeles in the San Joaquin Valley at the base of the foothills beneath Sequoia National Park. "We're sitting here trying to stop this thing, and it wants to keep pushing in."
The huanglongbing disease, which spoils the flavor of the fruit and ultimately kills the tree, has been found in all of Florida's 32 citrus-producing counties since its discovery there in 2005, causing about $100 million in damages, said Andrew Meadows, a spokesman for Florida Citrus Mutual, the state's grower trade association.
Huanglongbing has also been found in Louisiana, Mexico, Brazil and China.
Florida officials have warned that their $9 billion citrus industry could be wiped out in a decade if a solution isn't found to the disease, also known as citrus greening because of the sickly green cast it lends to infected fruit.
"That's why California is so alarmed," said David Hall, a U.S. Agriculture Department entomologist in Florida who worked on a team that sequenced the genome of the bacteria that causes citrus greening.
In California, the insect has so far been found among planted citrus trees in four southern counties, prompting quarantines that prohibit nurseries from shipping seedlings to other areas. Fruit grown in those counties also must be washed before it can be sold outside the quarantine zone.
Dogs trained to sniff out the pest found packages of curry leaves with psyllids in FedEx packages this summer in Fresno and Sacramento. Only the Fresno psyllids tested positive for huanglongbing.
The psyllid is not the only pest that could threaten California citrus. The state is also home to the glassy-winged sharpshooter, a threat to grapes but also capable of carrying a debilitating disease called citrus variegated chlorosis that has been spotted in Brazil.
California agriculture officials have also been locked in a decades-long struggle with the crop-eating Mediterranean fruit fly, which can harm citrus plants and hundreds of other fruits and vegetables.
But the potential devastation that could accompany a psyllid infestation is especially troubling for Mulholland and other citrus farmers, who have started building screens around the open-air nurseries where vulnerable seedlings are cultivated in rows of inverted plastic cones.
Allan Lombardi, who helps oversee 2,100 acres of pink-fleshed Cara Cara oranges, deep-red Fukumoto oranges and other high-value citrus as a manager with Central Valley grower Griffith Farms, said his company is scrambling to enclose its nurseries before the pest reaches the area, but that it's about two years from completion.
"If the disease shows up sooner than that, we'll have to have a Plan B, and I'm not sure what that will be," Lombardi said as he looked down a mountain slope and into a lush valley planted thickly with rows of oranges.
Associated Press writer Greg Risling in Los Angeles contributed to this report.
Copyright 2009 The Associated Press.