The Asian citrus psyllid is alive and well in Santa Barbara County, according to the Agricultural Commissioner’s Office. They found a psyllid in Goleta this summer, and on Sept. 1 and 2, two more were found in Carpenteria. A week later, on Sept. 9 and 10, two more were found in Summerland.
The tiny bug can transmit Huanglongbing (HLB)—a deadly disease, if you’re a citrus tree. HLB has ravaged orange groves in China, Brazil, and Florida. A report put together by the University of Florida figured that HLB has destroyed $1.3 billion in lost grower revenue, $3.5 billion in economic activity, and 6,500 jobs in the South. One detection led to the devastation of more than 30 counties in Florida alone over the space of a few short years.
“This has been called by experts in the citrus industry the worst threat to commercial citrus growers in the world,” said Jay Van Rein, spokesperson with the California Department of Food and Agriculture. “There is no known solution.”
The department has a two-pronged approach for dealing with the psyllids. First, spray the tree with the pesticide pentol, a contact insecticide that kills off adults hiding in the foliage. Then, soak the ground and roots of the plant with imidacloprid, a neonicotinoid. It’ll be drawn up into the plant, where it will kill off future generations coming along to feed on the citrus branches.
The insecticides are the first prong of that strategy. The second: tiny parasitic wasps—stingerless and smaller than a grain of rice. They target the eggs of the psyllid, ensuring that they never hatch in the first place. The state Department of Food and Agriculture uses both wasps and pesticides, along with countywide quarantines on citrus products, to buy time while researchers search for a cure or treatment for HLB.
The disease turns lemons and oranges green and withers the trees on which they grow. “It affects the fruits—the taste, the size, the quality,” said Rudy Martel, assistant agricultural commissioner for Santa Barbara County. “Eventually, the tree dies.” That takes three to five years.
The treatment? “There’s nothing you can really do besides removing the tree,” Martel said. “You want to remove [it] because otherwise it could become a reservoir for the disease.”
Martel confirmed that HLB has not yet been detected in Santa Barbara County. In Los Angeles, where it has been detected, it’s proven persistent and, so far, endemic. California’s second case of HLB was discovered in San Gabriel this July, according to the Department of Food and Agriculture. It had withered a kumquat tree in a residential neighborhood about 15 miles away from the initial 2012 discovery in Hacienda Heights.
This article appears in Oct 8-15, 2015.