Spotted wing drosophila pressure is high this time of year with primocane raspberry harvest in full swing under high tunnels at the Michigan State University research site. To manage SWD, it's important to pick ripe fruit frequently and also to remove and dispose of any unmarketable fruit, including any berries on the ground. Unmarketable fruit is collected and disposed of in a sealed plastic bag left in the sun to heat up thus preventing any SWD eggs and larvae present from developing into adults. This practice, along with daily picking has kept SWD larvae numbers minimal.
At the Michigan research site, new blackberry canes are now being tied up to trellises. This fall we’ll lay the swing-arm trellises down on the ground and cover the canes with row cover to help them survive the cold Michigan winter.
Russell E. Larson Agricultural Research Center
Pennsylvania Furnace, PA
Tour Penn State's High Tunnel Research and Extension Facility, where strawberries, raspberries, tomatoes and other crops are grown to study factors such as what types of plastics work best to manage plant growth, temperatures and pests; types of solar-powered automated venting options to better manage heat load; and nutrient needs of crops grown in high tunnels. Tours are part of "Ag Progress Days".
At the Ithaca, New York TunnelBerries research site, representatives from Wegmans supermarket consider how high and low tunnels can be used to produce blackberries and strawberries out-of-season with organic methods.
Journal of Economic Entomology: Exclusion Netting Delays and Reduces Drosophila suzukii (Diptera: Drosophilidae) Infestation in Raspberries by Heather Leach, Steven Van Timmeren, Rufus Isaacs
"Exclusion netting applied to commercial size high tunnels resulted in a significant reduction in overall D. suzukii infestation in raspberries, as well as a 3-wk delay in the average first detectable fruit infestation. Raspberry size and quality were not affected by the exclusion treatments, indicating that this approach can be an important component of growers’ response to invasion by D. suzukii in temperate climates."
Four blackberry varieties (Columbia Star, Natchez, Obsidian, Triple Crown) are being compared on a rotating cross arm trellis (also called swing arm trellis) in Michigan high tunnels. Obsidian and Columbia Star are the earliest ripening (started in late June) and the latest is Triple Crown (still fruiting in early August). The earliest types ripened before spotted wing drosophila became troublesome, whereas SWD larvae were seen in Natchez and Triple Crown fruit. Looking forward to tallying the yields!
Cornell University tunnel projects include a high density planting of black raspberries. Fruit Field Day attendees visited this project and more at the July 20th New York State Agricultural Experiment Station (NYSAES) Fruit and Vegetable Research Farm in Geneva, New York.