Controlling an Invasive Tree with a Native Fungus: Inoculating Ailanthus altissima (Tree-of-Heaven) with Verticillium nonalfalfae in Highly Disturbed Appalachian Forests of Ohio

Abstract

Abstract Highly disturbed forests are commonplace throughout the eastern United States and their residing composition and structure is reflective of their past land use. Management and restoration efforts are complicated by diverse and abundant nonnative invasive plants, including Ailanthus altissima. Verticillium nonalfalfae has been identified as a potential native mycoherbicide option for Ailanthus. To test the efficacy of Verticillium on Ailanthus we designed a study in highly disturbed forests of southern Ohio. At each of five sites, we monitored symptomology, mortality, and rate of spread of stem-inoculated Verticillium on Ailanthus in four inoculated plots and compared it to a control plot. We also monitored native plants for Verticillium symptomology and community responses to Ailanthus control. Our results suggest that Verticillium is an effective tool for controlling Ailanthus with no observed effect on native flora. Further, Verticillium naturally spreads through stands and mortality is slow enough that other resident nonnative invasive plants do not rapidly increase.