The California Department of Agriculture has begun ground treatments at 12 San Diego County sites to prevent the spread of Asian citrus psyllid.
There are 10 in the South ay Terrace neighborhood near Sweetwater Reservoir and two in Dulzura, 23 miles away, according to a department news release.
Employees will be treating citrus and closely related plants with Pyganic, an organic compound widely used in organic citrus groves. They also will be drenching the soil with Merit, a systemic imidaclorpid compound.
The properties were treated Sept. 17, with two more follow-up treatments of Pyganic at seven-day intervals.
At the same time, CDFA announced a quarantine in southern San Diego County to regulate the movement of host plants.
The concern is the Asian citrus psyllid is the primary vector of citrus greening, sometimes called huanglongbing or HLB, a deadly bacterial disease of citrus. So far, none of the trees on which the psyllid have been found have tested positive for the disease.
There is no cure for greening once trees are infected. Diseased trees produce inedible fruit, have reduced yields and eventually die. The bacteria is harmless to humans.
In addition to California, the psyllid has been found in Texas, Georgia, Mississippi, South Carolina, Alabama, Louisiana and Florida.
Since citrus greening was first identified in Florida in 2005, it has spread to all of its 32 citrus-producing counties. One tree near New Orleans also has tested positive for the disease. The tree was destroyed soon after.
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