Speaker:
Ann Brooks Gould, Extension Specialist, Rutgers University
Biography:
Ann Brooks Gould, a native of Chicago Illinois, received her B.S. (1978) and M.S (1980) degrees in biology from Illinois State University and a Ph.D. (1988) in plant pathology from the University of Kentucky. Subsequent work as a post-doctoral research associate at the University of Florida focused on the study of root-infecting pathogens of citrus, fruit crops, and woody ornamentals. Dr. Gould joined the Department of Plant Pathology at Rutgers University as an Extension Specialist in 1990, where her extension and research programs have focused on diseases of ornamental plants. Particular interests include bacterial leaf scorch of shade trees and Phytophthora root in ornamental nursery crops. Dr. Gould has an active outreach program, addressing disease management issues of importance to the nursery, landscape, greenhouse, arborist, Christmas tree, and turf industries. She also teaches an undergraduate course in plant pathology each year at Cook College.
Abstract:
Bacterial leaf scorch (BLS) of amenity trees, a vascular disease introduced to the northeastern US, has reached epidemic proportions in susceptible trees throughout the eastern regions of the United States. In New Jersey, the disease is widespread and has increased in incidence on oaks in the red oak group (Section Lobatae) in residential neighborhoods, municipal parks, golf courses, and woodlots. In 2002-2004 surveys, as many as 44% of oaks in several New Jersey municipalities are affected. Considering that the red oak group comprises 25 to 35% of the total street tree resource, surveyed communities will be expected to plan for and sustain losses up to $1.8 million within the next 5 to 10 years. With no current cost-effective rescue technology, arborists are forced to remove trees to prevent liabilities that may result from falling branches in declining trees. The biology and spread of BLS, caused by the bacterium Xylella fastidiosa, is complex and is determined in large part by the species of insects that vector the bacterium, bacterial strain, species/genetics of the host tree, and alternative hosts (plants that harbor Xylella and may serve as a reservoir for disease). Without a clear understanding of the disease, however, it is difficult to devise preventive or remedial strategies that community arborists can use to delay or manage the epidemic. In this presentation, I plan to describe the biology of this disease, discuss some current work in the area, and present options for management.