Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Attack dynamics and impacts of emerald ash borer on wild white fringetree populations.

Abstract

North American forests have been heavily impacted from the loss of ash trees (Fraxinus spp.) due to emerald ash borer (EAB, Agrilus planipennis) invasion. Recently, white fringetree (Chionanthus virginicus), an ash relative, has been found to support the development of EAB in ornamental plantings, but interactions between EAB and this plant have never been examined in wild populations. We monitored two wild white fringetree populations in Ohio throughout the invasion wave of EAB to examine its impacts and factors that increased the likelihood of attack. Within 2 years of study initiation, the majority of white ash (F. americana) were attacked by EAB in these areas, in contrast to a few individual fringetrees. By the end of 5 years, however, EAB attacked up to 30% of white fringetrees and caused branch mortality in several individual plants. The percentage of white fringetrees attacked was significantly lower than in white ash trees, the majority of ash died due to EAB. Those fringetrees that were attacked displayed signs of stress, including epicormic branching and canopy thinning, both symptoms of larval damage by EAB. Our results provide the first reported findings of the dynamics and impact of EAB on wild white fringetree populations.