@article{wilson_backe_just_lahr_nagle_long_dale_frank_2023, title={Tree species richness around urban red maples reduces pest density but does not enhance biological control}, volume={88}, ISSN={["1610-8167"]}, DOI={10.1016/j.ufug.2023.128093}, abstractNote={Urban trees often host greater insect pest abundance than trees in rural forests. This may be due, in part, to differences in tree diversity and canopy cover between these settings. Urban trees are often planted in isolation or monoculture, which favors pest accumulation. Gloomy scale, Melanaspis tenebricosa Comstock, is a pest of urban red maples (Acer rubrum L.) that is abundant where impervious surfaces dominate the local landscape. Increasing tree diversity and canopy cover around urban red maples may reduce gloomy scale abundance by supporting natural enemy communities. We investigated the effect that surrounding tree species richness and tree canopy cover had on gloomy scale abundance, natural enemy abundance, and biological control in red maple trees in Raleigh, NC, USA. We collected scales and natural enemies from red maples that spanned a gradient of tree species richness, canopy cover, and impervious surface values. We also measured gloomy scale parasitism and predation of sentinel prey in red maple canopies. Greater tree species richness and canopy cover were associated with lower gloomy scale density. Red maples in diverse settings also hosted fewer scales per natural enemy. Parasitoids were less common in maples in diverse settings, but generalist predator abundance was unaffected by tree diversity. Finally, tree species richness and canopy cover did not increase biological control of scales or sentinel prey. Our findings suggest that higher tree diversity and greater canopy cover may reduce gloomy scale density, but this is not entirely explained by the effects of natural enemies and biological control.}, journal={URBAN FORESTRY & URBAN GREENING}, author={Wilson, Caleb J. and Backe, Kristi M. and Just, Michael G. and Lahr, Eleanor C. and Nagle, Annemarie M. and Long, Lawrence C. and Dale, Adam G. and Frank, Steven D.}, year={2023}, month={Oct} } @article{long_frank_2020, title={Risk of bird predation and defoliating insect abundance are greater in urban forest fragments than street trees}, volume={23}, ISSN={["1573-1642"]}, DOI={10.1007/s11252-020-00939-x}, number={3}, journal={URBAN ECOSYSTEMS}, author={Long, Lawrence C. and Frank, Steven D.}, year={2020}, month={Jun}, pages={519–531} } @article{just_dale_long_frank_2019, title={Urbanization drives unique latitudinal patterns of insect herbivory and tree condition}, volume={128}, ISSN={["1600-0706"]}, DOI={10.1111/oik.05874}, abstractNote={Urban landscapes are characterized by high proportions of impervious surface resulting in higher temperatures than adjacent natural landscapes. In some cities, like those at cooler latitudes, trees may benefit from warmer urban temperatures, but trees in many cities are beset with problems like drought stress and increased herbivory. What drives patterns of urban tree health across urbanization and latitudinal temperature gradients? In natural systems, latitude–herbivory relationships are well‐studied, and recent temperate studies have shown that herbivory generally increases with decreasing latitudes (warmer temperatures). However, the applicability of this latitude–herbivory theory in already‐warmed urban systems is unknown. In this study, we investigated how the interaction of urbanization, latitudinal warming and scale insect abundance affected urban tree health. We predicted that trees in warmer, lower latitude cities would be in poorer health at lower levels of urbanization than trees at cooler, higher latitudes due to the interaction of urbanization, latitudinal temperature and herbivory. To evaluate our predictions, we surveyed the abundance of scale insect herbivores on a single, common tree species Acer rubrum in eight US cities spanning 10° of latitude. We estimated urbanization at two extents, a local one that accounted for the direct effects on an individual tree, and a larger one that captured the surrounding urban landscape. We found that urban tree health did not vary with latitudinal temperature but was best predicted by local urbanization and herbivore abundance. We did not observe increased herbivore abundance in warmer, lower latitudes cities, but instead herbivore abundance peaked in the mid latitudes of our study. This study demonstrates that urban landscapes may deviate from classical theory developed in natural systems and reinforces the need for research reconciling ecological patterns in urban landscapes.}, number={7}, journal={OIKOS}, author={Just, Michael G. and Dale, Adam G. and Long, Lawrence C. and Frank, Steven D.}, year={2019}, month={Jul}, pages={984–993} } @misc{klooster_gandhi_long_perry_rice_herms_2018, title={Ecological impacts of emerald ash borer in forests at the epicenter of the invasion in North America}, volume={9}, number={5}, journal={Forests}, author={Klooster, W. S. and Gandhi, K. J. K. and Long, L. C. and Perry, K. I. and Rice, K. B. and Herms, D. A.}, year={2018} } @article{long_d'amico_frank_2019, title={Urban forest fragments buffer trees from warming and pests}, volume={658}, ISSN={["1879-1026"]}, DOI={10.1016/j.scitotenv.2018.12.293}, abstractNote={Trees are important components of urban landscapes because of the ecosystem services they provide. However, the effects of urbanization, particularly high temperatures, can benefit chronic insect pests and threaten ecosystem services offered by urban trees. Urban forest fragments are an often-overlooked component of the greater urban forest which may help to mitigate the damaging effects of urbanization. Melanaspis tenebricosa (gloomy scale) is a common pest of Acer rubrum (red maple) that becomes more abundant because of the urban heat island effect. We conducted observational and manipulative field experiments to test the hypothesis that trees in urban forest fragments would be cooler than those in surrounding ornamental landscapes and would thus have fewer M. tenebricosa, particularly in a hot mid-latitude city. Trees in forest fragments were 1.3° cooler and had three orders of magnitude fewer M. tenebricosa than trees in ornamental landscapes in Raleigh, NC USA. However, there was no difference in M. tenebricosa density between forest and landscape trees in Newark, DE and Philadelphia, PA USA which are 3.95 degrees of latitude higher, and nearer to the northern range extent. Trees in landscapes and forest fragments did not differ in predawn water potential, a measure of water stress, but likely differed in soil composition and moisture. We used potted trees to control for these differences and found that M. tenebricosa density still increased three times more in landscapes than forests suggesting temperature and not tree stress is the dominant factor. Taken together our results indicate two things. First, that trees growing in urban forest fragments are buffered from a chronic urban tree pest due to lower temperatures. Second, that temperature-driven differences in M. tenebricosa density which we saw in Raleigh could predict future density of the pest in higher latitude cities as the climate warms.}, journal={SCIENCE OF THE TOTAL ENVIRONMENT}, author={Long, Lawrence C. and D'Amico, Vincent and Frank, Steven D.}, year={2019}, month={Mar}, pages={1523–1530} }