Verticillium nonalfalfae as a biological control agent for Tree of Heaven (Web-based)
Tree of Heaven is common throughout the much of the eastern U.S. This rapidly-growing tree can reach heights of 80', and can quickly dominate plant communities. Tree of Heaven produces chemicals in its roots that prevent other plant species from growing around it, thereby creating monocultural Tree of Heaven stands. This tree will grow most anywhere, including cracks in the sidewalk and in very dry areas. Tree of Heaven is very difficult to control, as it spreads both by seed (it is a prolific seed producer) and by root suckering and resprouting. When cut, the tree sends up large numbers of smaller shoots and root sprouts. Tree of Heaven can be controlled with herbicides. The biological control of Tree of Heaven has been a topic of interest since the discovery of a destructive naturally occurring Verticillium wilt disease of Tree of Heaven in 2002. The pathogen Verticillium nonalfalfae is currently being studied as a potential biological control agent of Tree of Heaven.