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Completed Project

Defending Against Extinction: A Comprehensive Management Plan to Combat the Emerald Ash Borer

Timothy Veit , Vassar College ’16, Naomi Sudo, Vassar College ’16 and Profs. Mary Ellen Czesak and Meg Ronsheim
Since its arrival in Michigan in 2002, the Emerald Ash Borer (Agrilus planipennis, EAB) has destroyed millions of ash trees (Fraxinus sp.) in North America. EAB is a beetle from Asia that kills ash by eating the phloem and preventing nutrient transport throughout the tree. To prevent the extinction of ash and mitigate environmental impacts of losing trees, various methods are being used to combat EAB. Because the borer has not reached the Vassar Farm and Ecological Preserve, the site offers a unique opportunity to implement a multi-pronged EAB management plan to preserve our ash, including seed collection, tree injections, and the use of egg parasitoids as biocontrol agents for EAB. Our main project this summer involved looking at the effectiveness of these egg parasitoids in controlling early EAB infestations. In June 2015 parasitoid wasps (Oobius agrili) provided by the USDA were released on 10 marked ash trees at a site near the Collins Field Station while a control site was established adjacent to Sunset Lake. Six weeks later, the release containers were collected and returned to the USDA for EAB egg parasitism analysis. 100m by 10m transects were established in late July at both sites to measure diameter at breast height (DBH), assess canopy health, and examine trees for signs of EAB. We found no evidence of EAB at Vassar, but sightings of the borer have been confirmed within 6 miles of campus, indicating infestation is likely in the next two years. The borer’s close proximity to campus means rapid implementation of a comprehensive management plan is essential in protecting our ash from extinction.