2010-04-02 / Health & Wellness

Disease could devastate backyard and commercial citrus trees

By Sophia Fischer sfischer@theacorn.com

GOOD FRUIT?—An orchard owner in Camarillo picks ripe oranges from a tree. Officials from the Farm Bureau of Ventura County are asking residents who own citrus trees to look out for symptoms of a plant-killing virus. Infected trees produce fruit that is bitter, misshapen and oddly colored. Acorn file photo GOOD FRUIT?—An orchard owner in Camarillo picks ripe oranges from a tree. Officials from the Farm Bureau of Ventura County are asking residents who own citrus trees to look out for symptoms of a plant-killing virus. Infected trees produce fruit that is bitter, misshapen and oddly colored. Acorn file photo Officials from the Farm Bureau of Ventura County are asking residents to be vigilant in checking their citrus plants for a fatal-disease-carrying pest that could decimate their backyard trees and wreak havoc on the local citrus-growing industry.

A Ventura County citrus farmer warned about the epidemic at a recent meeting of the Oak Park Municipal Advisory Council.

Citrus greening disease, also known as Huanglongbing or yellow dragon disease, attacks all citrus trees. Carried by a small insect called the Asian citrus psyllid, the disease has been found in Mexico and in some nearby states.

To stop the movement of potentially infected plants, all counties south of Ventura County have been placed under quarantine, including Los Angeles, Riverside, Imperial, Orange and San Diego.

While the psyllid was recently found in Van Nuys, no infected insects appear to have entered the county.

The psyllid is small, about the size of an aphid, and resembles a tiny newt. Infected trees produce fruit that is bitter, misshapen and oddly colored. The tree will eventually die. There is no danger to humans, animals or other trees and plants.

Citrus trees that are infected can die within five to 10 years, said Leslie Leavens-Crowe, president of the Farm Bureau of Ventura County.The pest spreads rapidly, she said.

“It is likely that the first find will be this end of the county this year and probably someone’s backyard tree, which is why it’s so important that everyone needs to become a citrus detective and inspect trees frequently for pests,” Leavens- Crowe said.

Leavens-Crowe’s family, which has owned farmland in the county for a century, has grown hundreds of acres of lemon and avocado trees since the 1950s. Ventura County’s 24,000 acres of commercial citrus groves represent about onefourth of the county’s total agriculture and provide more than 7,000 jobs and $19 million in tax revenue. A rapidly spreading disease would have major repercussions.

“It’s critical we get everyone on board,” Leavens-Crowe said. “We’re all in this together.”

The disease reportedly has taken out more than 200,000 acres of citrus in Florida.

“Florida was asleep at the switch and didn’t realize it was a big danger,” Leavens-Crowe said. “By the time they found it, it had already spread throughout the state.”

Alabama, Mississippi, Louisiana, Texas, South Carolina and Hawaii are under quarantine. The disease has devastated citrus crops in Asia, Africa, the Arabian Peninsula and Brazil.

“The only way to stop it is by killing the pest,” Leavens- Crowe said.

Eradication efforts include spraying a low-toxicity pesticide made from chrysanthemums on a 400-meter radius of the find and a second pesticide on the soil around the base of the infected tree, which must be removed.

State, national and international agencies are working together to detect the disease. Trapping and research efforts are being funded by the citrus growing industry, Leavens- Crowe said.

“We’re really trying to learn from Florida and trying to buy some time until research catches up and we can learn to live with the disease,” Leavens-Crowe said.

Fruit and citrus plants from other Southern California counties should not be moved, officials say.

Additionally, residents should buy only Californiagrown, certified citrus from reputable nurseries, and all new plants should have labels on them indicating that they have been inspected and are diseasefree.

If a plant originates from a quarantined area, that means it already has had two pesticide treatments, which are good for three months.

For details, visit the website www.californiacitrusthreat.org or call the California Department of Food and Agriculture hotline at (800) 491-1899.

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