More live Mediterranean fruit fly larvae were found Friday in Spanish clementines in Southern California retail stores, increasing concerns that the imported citrus could wreak havoc on the state's $27-billion agriculture business.
Although the small number of larvae found is unlikely to cause the type of infestation that cost the state $300 million to contain in the 1980s and early 1990s, it does raise questions about the effectiveness of current pest-control rules for imported citrus, industry officials say.
"We're very concerned," said Mike Wootton, a spokesman for citrus cooperative Sunkist Growers. "What this tells us is it's a systemwide failure. They have enough solid evidence to shut down the [imports] for the remainder of the season."
The Department of Agriculture on Wednesday banned imports of clementines from Spain, the largest producer of these seedless mandarins, after live Mediterranean fruit fly larvae were found in San Jose and in North Carolina, Maryland and Louisiana. And the USDA is sending representatives to Spain next week to look into the problem.
On Friday, live medfly larvae were found in retail stores in Riverside and, state officials believe, in San Diego. That sample is being sent to Sacramento for testing.
Supermarkets in 17 Southern states were ordered to pull the Spanish fruit from their shelves for fear that any live larvae would hatch and threaten growing areas. Although it does not pose a threat to humans, the medfly larva feeds on 260 different types of fruits, nuts and vegetables, making it one of agriculture's most destructive pests.
California officials have so far seized nearly 50,000 cartons of clementines from supermarkets and wholesalers and are directing them to Northern markets where the pest will not survive the cold weather.
State Agriculture Secretary Bill Lyons Jr. sent a petition Friday asking the USDA to require citrus-exporting countries to provide a set of pest-control protocols they will follow before shipping fruit, such as baiting and trapping, fumigation, and pre-shipment sampling.
But growers say just as important is reviewing the pest-control methods that the USDA requires of citrus exporting countries, especially the cold-treatment method used on ships bringing oranges and other citrus into this country.
This method, which uses near-freezing temperatures in containers to kill the medfly and other pests, is being called into question now that live larvae are being found in markets served by different ports and different boats.
Spanish agriculture officials say they don't have a problem with fruit fly infestation. However, a November report by the USDA's Foreign Agricultural Service noted the presence of the pest in that country.
It's not the first time in recent history that fruit flies or their larvae have been found in the state, according to Steve Lyle of the California Department of Food and Agriculture.
Earlier this year, medfly larvae were found in a grapefruit in the backyard of a home near Inglewood. And the USDA said a medfly was found in 1997 in the Walnut Park area of Los Angeles County.
However, state officials say a trapping regimen and a $15-million prevention program that releases sterile bugs into these areas is keeping the pests from spreading to commercial growing areas.
Because the medfly larvae were intercepted at warehouses before they could hatch and multiply in growing areas, state officials believe they can head off a crisis.
Meanwhile, California growers are beginning to enjoy a financial boost as supermarkets have begun looking for other citrus products to replace Spanish clementines on the produce aisle.
Orange Cove, Calif., mandarin grower Tom Mulholland said he has seen a spike in demand for his fruit in the two days since the ban, even though his prices are much higher than than those for the Spanish fruit.
Many retailers, he said, had advertised mandarin oranges and are now having to stock locally grown fruit.