Pest management of agricultural insect pests has often been focused on utilizing chemical control methods. However, managing habitats within and surrounding the crop field at varying spatial scales can be an effective and more sustainable means of controlling insect pest populations. In this thesis, I investigated the impacts of the surrounding habitat and landscapes on the overwintering biology and population dynamics of the common asparagus beetle (Crioceris asparagi L.) in commercial asparagus agroecosystems. During the winter of 2019-2020, I found that a majority of asparagus beetles were overwintering within asparagus fields, with beetle abundance being 23 times higher than field margins and 8 times higher than surrounding woodlots. In field experiments, asparagus beetle overwintering survival was highest when using deciduous leaves as overwintering habitat and decaying hollow asparagus stalks also provided overwintering shelter. At a landscape scale, the effect of the surrounding landscape varied between Oceana and Cass counties. While the proportion of asparagus was the only parameter that had an effect on asparagus beetle abundance in Oceana county, each landscape variable influenced beetle abundance in Cass county. When counties were combined, the proportion of semi-natural habitat (deciduous forest, evergreen forest, grassland) surrounding commercial asparagus fields was positively related to the abundance of asparagus beetles in asparagus fields. These results demonstrated that semi-natural habitats can potentially provide resources to not only beneficial insects, as previously thought, but pest populations as well. Both edge density, the number of edges within an area, and Shannon’s Diversity Index (SHDI), the diversity and evenness of land covers, were positively related at lower spatial scales (100-200m) and negatively related at higher spatial scales, (300-2000m) to the abundance of asparagus beetles in asparagus fields. Ultimately, my results suggest that both local and landscape level factors are influencing the overwintering biology and population dynamics of the common asparagus beetle.
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