Adult spotted wing drosophila.

MN Impact: High Tunnels Help Protect MN Crops from SWD

January 18, 2019

Objective

Research will support new horticultural crops' growth.

Issue

Since its arrival in 2012, the spotted wing drosophila (SWD) has been one of the most damaging invasive species in Minnesota agriculture. SWD has damaged locally grown small fruit crops, shortened pick-your-own seasons, increased pesticide use and reduced incomes for producers.

What has been done

Bill Hutchison and his team are exploring several management practices to help Minnesota small fruit growers deal with this devastating threat. Included in their studies have been fruit preference tests, comparing the effectiveness of various insecticides and exploring how plastic and/or exclusion netting on high tunnels (HT) might assist in keeping these small pests at bay.

Results

2017 research trials documented 98-100 percent reductions in SWD numbers and/or berry infestations using a HT approach in both raspberry and grapes (this included using a traditional plastic cover on top and ventilated exclusion netting on the sides and ends).

Researchers and extension specialists are sharing these results with growers, along with best practices, and are working on updated cost estimates to help local growers decide if this will be a useful management option for their needs.