Spray protocol, quarantine in place for Kern County
By CECILIA PARSONS
For the Capital Press
The unusual find of a melon fruit fly in a rural and agriculture-rich section of Kern County threatens to jeopardize harvests.
Concerned growers filled a meeting hall in the Kern County community of Lamont Aug. 18 to learn the impacts of a state and federal quarantine zone put in place in an effort to contain the agricultural pest. The 82-square-mile quarantine zone encompasses thousands of acres of commercial production.
On Aug. 10, five melon fruit flies were detected in a single trap in a commercial agriculture area in southeastern Kern County. The find was highly unusual, California Department of Food and Agriculture biologist Art Gilbert told growers, because invasive pests are normally transported by humans and they are more commonly found in residential areas.
The five flies, confirmed as wild by CDFA, were trapped in a county detection trap placed in a pepper field. On Aug. 11, an additional fly was trapped close to the first find. The only previous find of melon fruit fly in California was in the Los Angeles area.
"These pests come in with people," said Gilbert, who added that an investigative branch of the USDA is working determine the source of the infestation and officials are interviewing nearby residents.
Meanwhile trapping for the pest has intensified with 8,000 detection traps placed within a mile of the melon fruit fly find. Kill traps for adult male flies are also being set.
Cliff Ramos of CDFA said the agency is also cutting fruit in a 200-meter zone around the find, but no larvae have been detected.
Melon fruit flies, native to Asia, are the most destructive pest of melons and squash worldwide. Larger than a housefly, the melon fruit fly is reddish yellow and has brown spots on its wings.
Female melon fruit flies lay eggs under the skin of host fruit. When the eggs hatch, the larvae tunnel into the fruit, making it inedible. The larvae are white. Besides Southeast Asia, the melon fruit fly is found in Africa and India and has been introduced in Hawaii.
Dealing with the pest has already led to some crop loss, according to Kern County Agriculture Commissioner Ruben Arroyo.
The pepper field and fruit trees on adjacent residential properties were stripped with assistance from the California Conservation Corps.
Arroyo said most of the melon harvest had been completed in the area before the flies were detected. Any remaining host crops in the area that must be harvested within the next 30 days will also be lost because of the required spray protocol. Crops that can wait until the 30-day pesticide spray protocol is complete can legally be harvested and transported from the quarantine area.
"Luckily, we have earlier harvests and most of the crops that would be affected are already out," Arroyo said.
Catarino Martinez of ValMar Farms said part of his peppers would not be harvested due to the quarantine.
The list of host crops includes peaches, citrus, cucumbers and tomatoes. Listed fruits or vegetable crops that will be processed can be harvested as long as growers, harvesters, haulers and processors sign a compliance agreement that lists precautions to prevent the spread of the pest. For instance, trailers would have to be tarped and free of green waste.
Growers with crops that have not been harvested now have to deal with a spray protocol that may not end until next April. If additional flies are trapped the quarantine area would be expanded and pesticide sprays would be mandated for a longer period.
Pre-harvest, growers of host crops must now spray either Malathion or Spinosad formulations specified by CDFA at 10-14 day intervals over a 30-day period. Spinosad is a material allowed in organic production; growers would be able to maintain their organic certification.
There is no reimbursement for costs of spraying. Other options include methyl bromide fumigation post harvest or processing on site.
Growers who export their crops also voiced concerns at the meeting that foreign buyers may shy away even if the crop is not on the host list. Grape growers asked if Australian buyers were being given current information.
Information on the spray protocol can be obtained from the CDFA Pest Hotline at 800-491-1899.
A detailed map of the quarantine area can be found at www.cdfa.ca.gov/phpps/PDEP/treatment/treatment_maps.html