Volume 13, Issue 1 - spring 2020
New urban forest research sheds light on the risk of pest invasions
Most urban forests are not well understood. What trees are there, where are they, and how many? Characterizing urban forests is crucial in order to assess the spread and impacts of invasive pests. Threat Center scientist Frank Koch, Center collaborator Mark Ambrose, and colleagues addressed the lack of urban tree data using a three-step modeling approach. As a test, they mapped distributions of maple, ash, and oak trees in urban areas across the eastern and central U.S. They modeled relationships between tree inventories and canopy cover, climate factors, and demographic trends. This allowed them to estimate the total number of each tree type, even if an urban area had no tree inventory or an incomplete one. The results were described in the journal Forest Ecology and Management. Now, the team is adapting the model to map the distribution of street palms around the U.S. ahead of any invasion by a major pest such as the coconut rhinoceros beetle or the red palm weevil. These insects are globally important agricultural pests, but their U.S. impact would be largely in urban areas where palms line the streets. The costs of removing and replacing infested palms could be substantial in places like south Florida, where street palms are common. Learn more about this research.