Diseases of Shade Trees

Book excerpt: Diseases of Shade Trees provides an introduction to tree diseases for students and others concerned with the care of shade and ornamental trees. Diseases of woody plants fall into two major categories: infectious diseases and noninfectious diseases. Part I of the book presents the infectious pathogens and the diseases they cause. These include bacteria, mycoplasmas, nematodes, seed plants, and viruses. The nature of the fungi is also presented, with separate chapters for leaf, root, rust, stem, and wilt diseases caused by fungi. Wound diseases, which are associated with both fungi and bacteria that invade wounds, are included in this section. Part II deals with noninfectious agents and the diseases they cause. Noninfectious agents are separated into environmental stress, animal injury, and people-pressure diseases. Diebacks and declines—complex diseases, which are often caused by a combination of both infectious and noninfectious agents are also included in this section. Part III on special topics includes discussions of nonpathogenic conditions often mistaken for diseases; diagnosis of tree diseases; and living hazard trees.