SACRAMENTO — The recent discoveries of Asian citrus psyllids in the Central California communities of Dinuba and Wasco have state agriculture officials fearing the infestation is more widespread than they first thought.
Hundreds of psyllids at all stages of development were found on young citrus trees last week in a residential neighborhood in Dinuba, prompting the California Department of Food and Agriculture to begin intensive trapping and treatments within a 1-mile radius of the find.
On the outskirts of Wasco, a single adult male psyllid was trapped on Sept. 5, prompting state officials to trap citrus trees within a wider radius, said Nancy Holland, the deputy director of Kern County’s agricultural commissioner’s office.
The measures come after a quarantine was put in place near Porterville, Calif., in response to the discovery of six psyllids there in June.
“We are very concerned” about a wider invasion of the pest that carries the deadly tree disease Huanglongbing, said Steve Lyle, a CDFA spokesman.
“We’re fortunate that, if there is a silver lining, we just have the pest and not the disease,” Lyle said. “But we believe it’s just a matter of time before the disease becomes established. It puts pressure on us and our partners at the USDA and in the counties involved ... to do our best to deal with these infestations in the Central Valley.”
The latest discoveries will likely prompt quarantines like the one imposed in areas near Porterville, which encompass 178 square miles. Under a quarantine, nursery stock are prohibited from being shipped except for nursery stock and budwood grown in USDA-approved structures designed to keep the psyllid out.
All citrus fruit in a quarantine zone has to be cleared of leaves and stems prior to moving out of the area. Residents with backyard citrus trees in a quarantine area are asked not to take fruit out of the zone.
No major agricultural nurseries would be affected by a quarantine in the Dinuba area, though several small nurseries exist in the region, said Gavin Iacono, a Tulare County deputy agricultural commissioner. Officials believe psyllids came into the area aboard a young tree that was given to a resident as a gift, he said.
In Wasco, no commercial citrus operations exist within a five-mile radius of the psyllid discovery, Holland said. The CDFA was slated to meet with residents Sept. 18 to discuss treatment plans, she said.
In all, more than 45,000 square miles within California are already under an ACP-related quarantine, including areas in Ventura, Santa Barbara, San Diego, Imperial, Orange, Los Angeles, San Bernardino and Riverside counties, according to the CDFA.
Asian citrus psyllids were trapped for the first time in the state’s citrus belt last November, causing the state to initially restrict movement of citrus within a 20-mile radius of the finds before the area was reduced to five miles.
CDFA Asian citrus psyllid information: http://www.cdfa.ca.gov/plant/acp/index.html