Official Pest Report

Official Pest Reports are provided by National Plant Protection Organizations within the NAPPO region. These Pest Reports are intended to comply with the International Plant Protection Convention's Standard on Pest Reporting, endorsed by the Interim Commission on Phytosanitary Measures in March 2002.

Oriental Fruit Fly (OFF) (Bactrocera dorsalis) in California

Country: United States

Title: Oriental Fruit Fly (OFF) (Bactrocera dorsalis) in California

Not available


Between September 23 and October 23, 2003, the Animal and Plant Health Inspection Service (APHIS) and the California Department of Food and Agriculture (CDFA) captured in excess of 9 adult OFF’s (Bactrocera dorsalis) in the Ontario area of San Bernardino County, California. The detection of numerous adult OFF’s is an indication of an incipient infestation in San Bernardino County. We are amending the Federal OFF regulations to include an area of San Bernardino and Los Angeles Counties because an OFF infestation was declared by CDFA on October 27, 2003. According to USDA eradication protocols and procedures, detection of two OFF’s within three and one half mile radius triggers a series of bait (methyl eugenol mixed with a small amount of insecticide) station treatments. In addition, detections in urban areas in excess of eight OFF’s within a three mile radius require regulatory action to prevent the movement of host material out of the quarantine area. The present infestation is limited to approximately 137 square miles surrounding the OFF infestation in the Ontario area of San Bernardino that includes a small portion of Los Angeles County (Pomona). 

A Proclamation of Eradication was issued by CDFA on October 7, 2003, for a treatment area of 13 square miles. An addendum to the Proclamation was issued on October 20, 2003, expanding the treatment area to include areas of additional OFF detections. According to eradication protocol, Jackson and McPhail trap density was increased to 25 per square mile in the core area. The area around each find will be treated according to male annihilation treatment protocol every two weeks for two life cycles, about 60 days, beyond the last OFF find. A visual survey of fruit fly host materials is being conducted to detect the presence of OFF larvae. If larvae are found, foliage of host plants will be treated with malathion bait spray on infested and adjacent properties. Fruit stripping and soil drenches with diazinon will take place on infested and adjacent properties. 

The infestation represents a threat to the agriculture and the environment of California and other U.S. citrus-producing States. APHIS is cooperating with CDFA in delimiting survey, treatment applications, regulation, and environmental monitoring. 

A program specific to the OFF Cooperative Program Environmental Assessment for the regulated area in San Bernardino County, California, has been completed and is available from local program managers or from the APHIS web page. 

Posted Date: Nov. 4, 2003, 9 a.m.