California's citrus farmers are asking homeowners to inspect their backyard citrus trees for symptoms of citrus greening, according to a Los Angeles Times article published today. The disease hasn't been reported in the state, but officials fear an illegally imported tree somewhere in the Southland might be a time bomb waiting for an Asian citrus psyllid to begin the disease's spread.

Asian citrus psyllid moved into the state from Mexico last summer. In other parts of the world, the pest has devastated the citrus industry by spreading citrus greening disease.

"The disease could be a catastrophe for California's $1.2-billion citrus industry," wrote Times reporter Jerry Hirsch. "Citrus greening has already killed tens of thousands of acres of trees in Florida and Brazil and wiped out entire citrus industries in China, India, Saudi Arabia and Egypt."

Researchers at UC Riverside, UC Davis, the University of Florida and other institutions are trying to find better ways to detect the disease in its long latent stage and to control the psyllid population, the article said.

According to a UC IPM Pest Note on Asian Citrus Psyllid, symptoms of citrus greening include yellow shoots and mottling and chlorosis of leaves. Infected trees are stunted, sparsly foliated and may bloom off season. Fruit do not color properly and the juice tastes bitter.

Homeowners and commercial landscapers who believe they have found Asian citrus psyllid or a tree infected with citrus greening disease should call the California Department of Food and Agriculture's exotic-pest hotline at (800) 491-1899.