The spotted wing Drosophila (SWD) is the latest insect pest to invade East Tennessee.

Joining the hemlock woolly adelgid, the emerald ash borer and the other insects that threaten crops and vegetation in the area, this Asian vinegar fly has spread to 23 Tennessee counties, from Greene County in the east to Gibson County in the west. It threatens commercial fruit crops such as strawberries, blackberries and blueberries.

While so far Blount County has been spared from an SWD infestation, it won’t be forever, said John Wilson, director for the UT-Blount County Extension Service. “It will arrive. It is just a matter of when. We are working with several fruit growers to monitor for SWD presence. It has been confirmed in East Tennessee.”

SWD was first detected in California in 2008. It reached blueberry crops in East Tennessee in 2011. The female SWD lays tiny eggs inside fruit, which hasten decomposition even before the larvae hatch.

The SWD targets strawberries, blueberries, blackberries, raspberries, grapes, figs, persimmons, cherries and other soft, thin-skinned fruit. Berries are especially susceptible. Wherever it has been found, the SWD has caused considerable damage to fruit crops, according to the University of Tennessee Institute of Agriculture.

Although researchers are looking for the best ways to control the pest, there are already some options. “There are some insecticide sprays and applications that one can make to their fruit crops to combat it,” Wilson said. “In our programs, what we call integrated pest management, what we like to do is not just make wholesale sprays of product or applications but to target applications when we have a known pest that is present.

“So right now we’re in a monitoring phase. We can use traps to monitor for their presence, and once we detect presence we can take action and make a timely application of an effective insecticide.”

Homeowners are not facing direct economic peril from potential SWD infestation damage, but prices could rise if harvests are reduced. “Locally, we’ve got folks producing apples and blueberries and strawberries and blackberries,” Wilson said. “That probably would be the primary effect if there was a significant or sustained crop injury that resulted in less available fruit.”

According to Frank Hale, a UT Extension entomologist, the first step in detecting whether the pest is present is setting traps within fruit crops baited with yeast, sugar and water. If detected, weekly insecticide applications should begin as soon as the fruit show the first sign of their ripening color, he said.

Source - http://www.thedailytimes.com/