Managing an oak decline crisis in Oakville, Ontario: lessons learned

Abstract

The town of Oakville, Ontario, is located along the north shore of Lake Ontario between Toronto and Hamilton. In the fall of 2002, significant oak (Quercus spp.) mortality was observed at Oakville's Iroquois Shoreline Woods Park, an environmentally significant forest remnant noted for its oak-dominated forests. Investigations suggested that oak decline was responsible for the widespread mortality and that other nearby forest lands were also affected. Oak decline is a disease complex brought on by multiple stresses (e.g., drought, defoliation, high stocking, tree senescence) and secondary pests such as Armillaria root rot (Armillaria gallica) and twolined chestnut borer (TLCB), Agrilus bilineatus. We present a case study that describes the steps that were taken to assess the situation, communicate issues to the public, resolve critical problems (e.g., salvage and hazard reduction), employ trap-tree strategies for TLCB, and develop silvicultural and restoration strategies that include aspects of oak management, regeneration, and prescribed fire. From a municipal forestry perspective, the most important aspects that led to a successful program were accessibility to experts with practical experience and development of effective communication strategies. This is a good case study for municipal foresters who must deal with catastrophic tree mortality in their woodlands similar to that caused by emerald ash borer (Agrilus planipennis).

Parent Publication

• Proceedings, 18th Central Hardwood Forest Conference

Citation

Williams, Peter A.; McNeil, John W.; Gottschalk, Kurt W.; Haack, Robert A. 2013. Managing an oak decline crisis in Oakville, Ontario: lessons learned. In: Miller, Gary W.; Schuler, Thomas M.; Gottschalk, Kurt W.; Brooks, John R.; Grushecky, Shawn T.; Spong, Ben D.; Rentch, James S., eds. Proceedings, 18th Central Hardwood Forest Conference; 2012 March 26-28; Morgantown, WV; Gen. Tech. Rep. NRS-P-117. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station: 192-207.