At least 100 pests with the capacity to carry and spread a disease deadly to citrus trees have been found in California's major citrus-producing region, The Fresno Bee reports.
The pests have been identified as Asian citrus psyllids, or Diaphorina citri, sap-sucking bugs originating in Asia which have spread to other citrus growing regions, including the Middle East, Latin America and the US.
The discovery, made in Tulare County, has alarmed county and state agriculture officials, who stated on Tuesday 10 September that only two of the pests had been caught in insect traps in a Dinuba neighbourhood.
However, further investigation has revealed dozens of the pests on several residental citrus trees and intensified California's fight against citrus disease.
Gene Hannon, a Fresno County entomologist who inspected the discovery in eastern Dinuba, emphasised that the number of this particular pest was the most ever seen in San Joaquin Valley.
'It was incredible,' Hannon told The Fresno Bee. 'There were easily a dozen on just one small leaf.'
Agriculture officials have said this poses a serious threat to Californian's US$2bn citrus industry, which has spent millions on preventing the psyllids entering the San Joaquin Valley from southern California.
The trees where the discovery has been made have been chemically treated and a quarantine is expected to be announced next week.
