Diagnosing health problems of woody plants

摘要

From tumor-like growths on bark to tattered leaves, tree health issues can take a variety of forms, although pinpointing the exact cause can be tricky. On the flip side, what appears to be a serious problem may be a minor issue that won't cause any long-term damage. How can an arborist make the right call? "Many factors can cause trees to become unhealthy and lose their aesthetic value or die, including infectious diseases, insect infestations, environmental stresses or site problems," says Mark Vitosh, a district forester for the Iowa Department of Natural Resource's Forestry Bureau, who addressed this topic during the 2010 Shade Tree Short Course at Iowa State University in early March. "In many cases, more than one factor may be involved. A correct diagnosis of the problem is the important first step in trying to save an unhealthy tree."