Dr. James Downer

Recognizing and understanding diseases in shade trees, Dr. James

Jim Downer 2Wednesday May 4th, 11:15am, Urban Forestry/Risk Breakout (Main Street USA)

Trees catch, harbor and infect each other with diseases that are contagious, cause symptoms, shorten their lifespans and predispose them to failure. Disease caused loss of value to trees in the urban forest has not been accurately quantified, but it is significant, and increasing especially as the drought extends into an historic fifth year in Southern California.  Accurate diagnosis of tree diseases and an understanding of the physiology of disease development aids in developing treatment protocols that include adjusting arboricultural practices to maintain diseased trees.

Dr. James Downer has 31 years of experience as a horticulture and plant pathology Advisor with the University of California Cooperative Extension in Ventura County.    Dr. Downer’s academic training is from Cal Poly, Pomona, (BSc. horticulture & botany, 1981; MSc. biology with an emphasis in plant pathology, 1983; Ph.D. in plant pathology, 1998 from University of California, Riverside.

Dr. Downer’s research is focused on mulch, soil microbiology and disease suppression in mulched soils, diseases of shade trees and other landscape plants and cultural practices to maintain landscape plants.  Dr. Downer is a member of the American Society of Horticultural Science, the American Phytopathological Society, The International Soc. of Arboriculture, the Western Chapter of the ISA, the International Society for Horticultural Science, and the Entomology Association of Southern California.  Dr. Downer also serves on the Board of the Western Chapter ISA and currently holds the office of Past President.  Dr. Downer has a love of shade trees, tree work, wood working, gardening, horticulture and the general study of plants and plant biology