LIMINGTON, Maine (NEWS CENTER) -- All farmers could do was watch, because they didn't have to wait long before the spotted wing drosophila, a fruit fly native to northern Asia, made its way to Maine.
"It has been creeping across the country for the last five years so," stated Earl Bunting, owner of Doles Orchard in Limington. "All the researchers knew that it was coming, we just didn't get a lot of notice."
Late last September, a trap on Bunting's farm caught the first one. Now, they are being caught by the thousands everywhere traps have been set in the state.
What makes spotted wing drosophila different from its native cousins? These invasive insects lay their eggs in fruit when it is still green, ruining the fruit when it ripens, as opposed to laying their eggs in fruit that already is over ripe.
"We've never had to spray our raspberries before and now we have to spray them on a regular basis," Bunting explained about the added cost and headache these invaders have caused in such a short time. "Coming out and spraying these with an insecticide twice a week is not cheap, it is not convenient, but if we are going to have raspberries this time of year, it is what we have to do."
The spotted wing drosophila doesn't seem to have much of a taste for fruit with hard skins or flesh, so crops like apples, pears and pumpkins have not been impacted much according to David Handley, a small fruit and vegetable expert with the University of Maine Cooperative Extension.
"Last year we kind of caught a bye," said Handley. "We caught it late in the season, but we knew that it was likely to over winter here and that it was probably going to be an issue this year as they have been dealing with in Florida and the other southern states last year."
Where they were only catching a few dozen in traps last year, the numbers have exploded to thousands being caught in a single trap in a week's time. Unfortunately, the traps only work to tell scientists that the bugs are present, and are not effective enough to control their populations.
"It is a new pest," he explained. "We are still trying to figure out how to deal with it, and in order to figure that out we need to know what kind of populations we have, when it shows up, what kind of things seem to effect it, and that is the data we are trying to collect this season so next year we have a better plan of attack."
His advice to growers is to apply insecticide regularly to protect their crops, and if they are looking to add new plantings of berries or fruit trees, to plant varieties that ripen early in the season.
"The later in the season that you go, the higher the numbers are going to be," said Handley.
"We've had some growers say, 'I am going to grow early varieties and get as much of my crop done before the end of the season as possible, and when this thing shows up I'm going to walk away, cause it is not worth that effort.'"