Invasive Woody Plants and Their Effects on Arthropods in the United States: Challenges and Opportunities

Invasive plant introductions are increasing globally, and trends in human activity suggest these increases will continue. Although we know much about interactions between invasive herbaceous plants and arthropod communities, there is a dearth of knowledge examining interactions between invasive woody plants and arthropod communities. What information does exist shows that invasive woody plant relationships with mutualists (e.g., pollinators), herbivores, twig- and stem-borers, leaf-litter and soil-dwelling arthropods, and other arthropod groups are complex and hint at multiple factors influencing effects. These relationships warrant additional attention to allow better prioritization of species for research and regulatory review. Chinese tallow tree, e.g., is renowned for its attractiveness to honeybees, whereas reduced pollinator populations are found among other invasive woody plants such as privet. The unknown driving mechanisms and interactions that create these differences represent a substantial gap in knowledge and warrant additional research. Our objectives are to review current knowledge regarding invasive woody plants and their interactions with various arthropod groups in the United States, outline future research needs, and present a call to action regarding invasive woody plant research.