Agricultural practices generally create unfavorable environments for beneficial insects, resulting in declines of these insects in agricultural landscapes and risking a loss in valuable ecosystem services, such as pollination and biological control. Previous work has demonstrated that the establishment of flowering plants can provide the necessary resources to support beneficial insects in agricultural landscapes, which can enhance beneficial insect populations in these regions. This dissertation evaluates how patch size and on-farm establishment of wildflower habitat supports beneficial insects and their delivery of ecosystem services.To investigate the response of insects to wildflower patch size and plant richness, 12 native perennial flowering plant species were established in 25 replicated patches ranging in size from 1 to 100 m2. With no significant differences in bloom density or flower richness across patch sizes, in general wild bees were observed at greater densities and higher diversity in larger patches. Conversely, honey bees and hoverflies did not respond to wildflower patch size, but all pollinators were positively influenced by increasing flower richness. Wildflower patch size was also important for natural enemy density, richness, and diversity. In contrast, there was only a slight increase in herbivore density with wildflower patch size.Through the investigation of pollination services delivered to three wildflower species with different bloom periods, patch area (positively), and floral richness (negatively), significantly influenced seed set of the measured wildflowers planted within the habitat patches. Comparing population growth of sentinel soybean aphids (Aphis glycines Matsumura) across wildflower patch size, aphid colonies were smaller as plot size increased, resulting in higher biocontrol service index values. Thus, providing beneficial insects with flowering resources resulted in significantly more beneficial insects and greater delivery of pollination and biological control services than in smaller habitat patches.Using highbush blueberry as a model system, wildflower plantings composed of 15 native perennial flowering plants and three native grass species were established adjacent to crop fields and evaluated for their efficacy at enhancing beneficial insect populations and their delivery of ecosystem services to the cropping system. Honey bees visiting blueberry flowers had similar abundance in enhanced and control fields, whereas wild bee abundance after three years was higher than in control fields. Pollination parameters including percent fruit set, berry weight, and mature seeds per berry were significantly greater in fields adjacent to wildflower plantings three and four years after seeding, leading to higher crop yields with value exceeding the cost of establishing and maintaining the plantings. Wildflower plantings also positively affected the density and diversity of some natural enemy groups and enhanced biological control of sentinel pest eggs along the crop edge. Conversely, insect herbivore densities generally were not enhanced by the provision of perennial floral resource plantings.The general patterns observed here can help guide future efforts in the conservation and support of beneficial insects in the natural and agricultural landscapes. The results from these studies suggest that small modifications to resource-poor, non-cropped areas within farms, such as through the establishment of native flowering plants, can selectively enhance biodiversity, pollination, pest-control, and thus has the potential to optimize multiple ecosystem services.
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