The Berry Patch Pioneers Innovative Use of Exclusion Netting
to Combat SWD
The Berry Patch, in tiny, rural Stephentown, has pioneered an innovative solution to spotted wing drosophila (SWD) infestation. Since it arrived in the United States in 2008, SWD has made it virtually impossible to grow commercially acceptable, pesticide-free raspberries and blueberries, but the Berry Patch’s experiments with exclusion netting seek to end crop losses.
Spotted wing drosophila is native to Southeast Asia. It first appeared in California in 2008, and spread to Florida the following year. By 2010, SWD had migrated to the Carolinas, Louisiana, Utah, Michigan, and Wisconsin. Northeastern fruit growers first went to battle with the insect in 2012, when an average of 80% of raspberry and 30% of blueberry crops—and approximately $4.3 million in revenue in NY state alone—were lost due to infestation of the fruit during its early ripening stages. Dale-Ila Riggs, co-owner of the Berry Patch and NYSBGA board chair, says, “This pest is a game-changer for berry growers nationwide. There are no natural enemies for it in the U.S.”
In 2012, Riggs lost about 40% of her lucrative blueberry crop to SWD. After observing some early research on the use of exclusion netting at Cornell University’s New York State Agricultural Experiment Station in Geneva, she obtained a Northeast Sustainable Agriculture Research and Education Farmer grant to test the use of the netting on her half-acre blueberry planting. Riggs adapted her existing bird-netting support system into a support system for the exclusion netting, with extra protections and anchoring to withstand thunderstorms, hail, and up to 60 mph winds. She then compared the fruits from the covered plot to the fruits grown in a control plot protected only with bird netting.
The results were startling. Riggs documented an infestation rate of 0.7% and 0.3% in 2014 and 2015, and last year had a 0% infestation rate—a rate virtually unheard-of in agricultural systems. Other farms around the country are taking notice, and have started to duplicate the Berry Patch’s successful growing system.
Riggs will set up her blueberry exclusion netting again in early July, prior to SWD’s summer activity. She also plans to experiment with the same exclusion netting for her high-tunnel raspberry planting for the first time this year. “With SWD, no one has been able to grow pesticide-free berries that are free from infestation,” Riggs notes. “The netting makes it possible. This is a highly effective method that brings new hope for growers.”