No differences in fruit set, berry weight, seed number, nor estimated yields were observed across treatments. Preliminary data from this project show that our border treatments have small to negligible impacts on our measured variables. Interestingly, we observed declines in arthropod populations that coincided with pesticide applications. Thus, in-field management practices, namely pesticide applications, appear to be driving arthropod diversity, not border vegetation. Despite these results, we did observe slightly greater arthropod diversity in our herbaceous border habitat treatment. This mirrors the work performed by Blaauw and Isaacs (2014 and 2015) in Michigan where diverse border habitats were associated with greater numbers of beneficial arthropods than pests. In their case, borders were intentionally seeded with wildflowers providing not only increased nectar and pollen, but the waist-high plants also provided protection. Intentionally planting flowering borders may increase arthropod diversity, but as long as SWD is managed with weekly sprays, any benefits will likely be negated. Currently growers will likely maintain their weekly SWD spray programs to ensure larvae-free berries until permanent changes in SWD populations are observed.
Funding for this project was provided by WSU’s BIOAg program. Thanks to Sean Watkinson and Clara TeVelde for assistance with data collection. Also, thank you to our grower collaborators.
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