Quantifying the Potential of Native Plants for Improving Pollination and Biological Control in Agroecosystems

Abstract

Agricultural areas can be inhospitable to the attraction and maintenance of beneficial insects like natural enemies and pollinators and this can result in a decrease in the ecosystem services of pollination and pest control that these insects supply. If habitat can be created and maintained on-farm, an increase in the numbers and diversity of beneficial insects could be seen which could correspond to an increase in ecosystem services. This study was undertaken to quantify what insect communities are supported by a set of native Oregon plants and to test for differences in the relative attractiveness of plant species to three broad categories of insects: herbivores, natural enemies, and pollinators. This first season of research shows that plant species vary in their relative attractiveness to the three functional groups of insects. Some of this variation is likely related to differences in flowering phenology. There was a significant positive association between percent peak bloom and the number of natural enemies collected on a particular plant species. The numbers of natural enemies, herbivores, and pollinators collected on plant species also varied across sites, suggesting that landscape characteristics also influence the insect communities associated with particular plant species.