Association and abundance of insect taxa in response to floral strips in an apple orchard

Abstract: In Canadian apple orchards, floral strips are typically established along borders,
where they are known to increase arthropod diversity near them. To evaluate whether we could extend this benefit within orchards, strips of native perennial flowers were established in the alleyways of four plots in an experimental, unsprayed orchard in Québec, Canada. Their effects on the abundance of different arthropod taxa were compared with four unmanaged control plots. Arthropod communities were sampled weekly over three growth seasons using pitfall traps (2021-2023), and over two growth seasons using aspiration (2021-2022). Across the three years of pitfall trap sampling, carabid beetles were almost twice as abundant in floral strips compared to controls. Across both sampling years, the aspiration data revealed that floral strips were associated with more Heteroptera, and non-Coccinellidae Coleoptera, and with less Homoptera. Additionally, Coccinellidae were more abundant in floral strips in 2021, and Brachycera in 2022. Our results support the use of alleyway floral strips as a useful habitat management strategy to promote and diversify beneficial arthropods in apple orchards.