[Featured Image Provided by Portland Parks & Recreation]
Invasive species are something our staff and volunteers are all too familiar with. Invasive English ivy, for example, is something we are constantly working to keep under control in Forest Park. However, we may have a new threat to contend with.
The emerald ash borer, Agrilus planipennis, is a species of beetle native to Asia that has found its way to the United States. It was first detected in the US in Michigan in 2002 and was first identified in Oregon in 2022. These beetles are an immense ecological threat, capable of devastating habitats including ash trees, like the native Oregon ash (source: Oregon State University). Additionally, emerald ash borer infestations have cost communities billions of dollars for treatment and replanting efforts necessary to offset the damage caused by the establishment of this insect in the United States (source: Colorado State Forest Service).
With emerald ash borers now in Oregon, this has necessitated a response to slow their spread and mitigate their impact on our local forests and parks. As part of Portland Parks & Recreation’s “Protect the Best” Invasive Vegetation Management Program, 14 emerald ash borer traps (see the featured photo) have been installed in multiple city parks for monitoring purposes, including Forest Park and Marquam Nature Park. As emerald ash borer populations spread within the state, these types of monitoring efforts are important for identifying locations that have become populated by the beetle.
The traps are large, purple, triangular constructions equipped with a pheromone lure and a strong glue. The lure attracts emerald ash borers and, while no insecticides are used in the construction of these traps, the glue prevents the beetles from escaping the trap. These traps will be periodically checked throughout the summer by Portland Parks & Recreation staff to see if emerald ash borers are present in any parks and, if they are, how many individuals were found at each park. The specimens will then be sent to the Oregon Department of Forestry for verification.
While this insect is potentially threatening to many of our favorite parks, take heart that work is being done to assess the threat and respond to it. Do you want to learn more about emerald ash borers, including steps you can take to help mitigate the spread of the emerald ash borer? If so, you can view an informational brochure produced by the Oregon Department of Forestry and some of the sources cited in this article below.
Sources:
Colorado State Forest Service. (n.d.). Quick Guide Series Emerald Ash Borer. https://www.centennialco.gov/files/sharedassets/public/v/1/documents/residents/emerald-ash-borer/emerald-ash-borer-quickguide.pdf
Oregon State University Extension Service. (2024, April 9). Emerald ash borer resources. OSU Extension Service. https://extension.oregonstate.edu/collection/emerald-ash-borer-resources
EAB Brochure: https://forestparkconservancy.org/wp-content/uploads/2023/05/EAB-Pocket-Guide.pdf