Last July, at the peak of cherry season, the European cherry fruit fly was trapped for the first time in commercial cherry orchards in Western New York, in the midst of harvest, sending a handful of growers and the regulators into uncharted territory.
A major pest in Europe, the fly was first detected in Ontario, Canada, in 2016 and across the river in Niagara County, New York, in 2017, in wild hosts such as honeysuckle and chokecherry. Federal officials issued a regional quarantine but had expected that commercial management practices in place to control native cherry fruit flies and spotted wing drosophila would be sufficient to control the invasive fly in commercial blocks.
But that has turned out not to be the case.
“We found it in five commercial orchards where growers are completely on top of their spray programs,” Margaret Kelly, assistant director of the plant division of the New York State Department of Agriculture and Markets, told concerned growers at a field day organized by Cornell Cooperative Extension in July. With a quarantine pest, a single fly found in a trap is enough to shut down harvest in a block. No infected commercial fruit was found.
The state tried to work with U.S. Department of Agriculture’s Animal and Plant Health Inspection Service, APHIS, to strike a balance between preventing movement of the fruit fly and allowing growers to get their fruit to processors and other markets, she said, but harvest arrived amid regulatory uncertainty.
“Plans were never really made for what happens if and when we find one,” said Jim Bittner, who farms in Appleton, New York. He’d just sprayed his tart cherry blocks with Ethrel (ethephon), to prepare for harvest, when APHIS found a positive trap catch in one block, despite his aggressive spray program.
After some tense back-and-forth with federal regulators, he and his processor got the go-ahead to harvest for juice processing, since the steam treatment involved was expected to kill any larvae that may have been present. He also had to shut down a 15-acre block of pick-your-own sweet cherries, which are a small but important part of the farm’s business, he said.
This year, APHIS and the New York State Department of Agriculture and Markets had a chance to plan ahead for how commercial growers can harvest and sell cherries in the midst of the quarantine designed to prevent the pest from spreading to other regions of commercial cherry production. The quarantined area, encompassing Niagara, Erie and part of Orleans counties, contains more than 500 acres of cherry production.
APHIS plans to “offer commercial cherry producers more options for managing the risk associated with domestic movement of fresh cherries quarantined for European cherry fruit fly,” APHIS said in a statement to Good Fruit Grower in April. The agencies will also evaluate pesticide effectiveness against the invasive fruit fly.
Having more pesticide options approved for control is welcomed, Bittner said, as is the sense that officials have given up the hope of eradication. Last summer, he worried the quarantine regulations were going to put cherry growers in his area out of business, trying to protect larger industries on the West Coast, and that the sacrifice would be fruitless since the fruit fly appeared to already be well established in natural areas along the shore of Lake Ontario, where host plants such as honeysuckle and chokecherry are common. Managing it there is far harder than in commercial orchards.
“It’s not an economic pest,” Bittner said. His pesticide regime has been able to keep fruit protected — as salt water tests showed. He and his neighbors want to do their part to keep it contained and also keep farming, he said.
Now, APHIS agrees that the European cherry fruit fly has become established in the Niagara area of New York, so the emphasis of the control program will continue to focus on preventing spread, but not eradication. Officials plan to expand surveillance to areas in New York and Michigan along the Canadian border and in Pennsylvania where tart cherries from the Niagara area are processed. •
—by Kate Prengaman