Hedgerows surrounding organic apple orchards in north‐west Spain: potential to conserve beneficial insects

Flowering plant species in hedgerows may be food sources for beneficial insects and therefore play a role in biodiversity conservation and agroecosystem functioning. Research was conducted in eight organic cider‐apple orchards in Asturias (north‐west Spain) aiming to (i) identify the native flowering plants in the surrounding hedgerows and (ii) assess the attractiveness of those flowers for beneficial insects, such as pollinators and natural enemies of pests. A total of 7745 flowers belonging to 63 plant species were recorded in the hedgerows from May to September 2012. Flower abundance and species richness decreased as the season progressed. Orchard differences were observed for plant species richness but not for the total number of flowers in the hedgerows, likely as a result of similar management among orchards. Hymenoptera pollinators (honey bees, bumblebees and wild bees) accounted for 37.8% of the total insects recorded visiting flowers, whereas predatory hoverflies (14.9%) were the dominant natural enemies. The attractiveness for insects was assessed for 21 of the flowering plant species identified in the hedgerows. Flowering plants differed in the number of taxa that they attracted and in their attractiveness for particular insect groups and for insects as a whole. The present study described the floral composition of the hedgerows that surround apple orchards and identified the local floral resources that could provide benefits for farmers by improving ecosystem services of pollination and biological control of pests.