Thousand Cankers Disease / Walnut Twig Beetle
Thousand cankers is a recently recognized disease of certain walnuts (Juglans spp.). The disease results from the combined activity of the walnut twig beetle (Pityophthorus juglandis) and a canker producing fungus in the genus Geosmithia (proposed name Geosmithia morbida). At present (2009) the disease is thought to be restricted to the western United States where over the past decade it has been involved in several large scale die-offs of walnut, particularly black walnut, Juglans nigra.
This disease was first recognized and described in 2008 by Ned Tisserat and Whitney Cranshaw of the Department of Bioagricultural Sciences and Pest Management.
Tisserat, N., W. Cranshaw, D. Leatherman, C. Utley, and K. Alexander. 2009. Black walnut mortality caused by the walnut twig beetle and thousand cankers disease. Plant Health Progress. August 11, 2009. 10 pp. (This is the original description of the disease in a peer reviewed journal) http://www.plantmanagementnetwork.org/php/elements/sum.aspx?id=8033&photo=4600
Thousand Cankers Disease: An Unusual Paradigm - June 2011, American Nurseryman
Fact Sheets:
Questions and Answers about Thousand Cankers Disease of Walnut
Pest Alert – Walnut Twig Beetle and Thousand Cankers Disease of Black Walnut
Diagnosing Thousand Cankers Disease of Walnut
PowerPoint Presentations on Thousand Cankers Disease/Walnut Twig Beetle
Walnut in the West:
Diagnosing Thousand Cankers Disease. Ned Tisserat May 2011
Thousand Cankers Disease - Annapolis. Ned Tisserat. January 2011
Nightmare on Walnut Street: Thousand Cankers Disease as an Emergent Threat to Juglans. Whitney Cranshaw. Presented at the International Society of Arboriculture Conference, Chicago, IL July 27, 2010
Walnut in the West: Death by a Thousand Cankers. Ned Tisserat. July 21, 2010
Issues Surrounding Thousand Cankers Disease and Its Management. Whitney Cranshaw. Presented at the First Conference on Thousand Cankers of Walnut, St. Louis, MO November 3, 2009
