Willow Hollow Golf Course: A Scenario Involving Gray Leaf Spot Disease

• Published in: Journal of natural resources and life sciences education 2002, Vol.31 (1), p.136-140
• Main Authors: Uddin, W., Turgeon, A. J.
• Format: Article
• Language: English
• Subjects: Environmental Influences; Management Systems; Problem Based Learning; Superintendents; Teaching Methods
• ISSN: 1059-9053; 1539-1582
• DOI: 10.2134/jnrlse.2002.0136

ABSTRACT Diagnosis and management of turfgrass diseases are some of the major challenges that turf managers routinely face in golf course operations. Although pathogens causing diseases of turfgrass may be present in the environment, outbreaks of disease do not occur unless environmental factors trigger the infection process in the presence of a susceptible host and a pathogen. When there is a change in environmental conditions, such as an increase or decrease in temperature and moisture, certain turfgrass pathogens favored by the prevailing conditions become active. Additionally, certain cultural practices not only influence pathogenic activity but also predispose the plants to attack by the pathogen. A serious outbreak of gray leaf spot disease epidemic at the Willow Hollow Golf Course in 1998 was an excellent example of how climate and culture interactively play significant roles in the development of a disease epidemic. In this scenario, the superintendent of Willow Hollow Golf Course, John Nairn, was unaware of the presence of the gray leaf spot pathogen, Pyricularia grisea. He did not expect a sudden outbreak of the disease, as the turfgrass appeared to be growing normally. In late August 1998 there were warm, humid conditions in southeastern Pennsylvania. John noticed that the fairways were off‐color and appeared moisture stressed; these conditions were soon followed by severe blighting of the turf. He concluded that this was probably due to summer heat and drought stresses. John began extensive irrigation to alleviate the stresses, but then discovered that this only exacerbated the problem. He immediately decided to seek help from a specialist at Penn State. When the problem was correctly identified, John was able to manage the existing disease effectively and avert consecutive epidemics that occurred throughout southeastern Pennsylvania that year. This scenario clearly demonstrates how an inaccurate diagnosis of a turfgrass disease can have devastating effects on a golf course, and how gray leaf spot epidemics can be prevented by timely disease diagnosis and correct management procedures. However, it also leads to broader discussions of alternate fairway turfgrasses and associated pest‐management systems. This scenario is a problem‐based learning (PBL) exercise that has been used with highly favorable results in an advanced turfgrass management course at Penn State University.