Development of regulatory treatments for thousand cankers disease

PARTNERS: USDA Forest Service Forest Health Protection (Southern Region); University of Tennessee; USDA Animal and Plant Health Inspection Service Center for Plant Health Science and Technology; USDA Forest Service Southern Research Station

SUMMARY: Thousand cankers disease (TCD) is a pest complex caused by the walnut twig beetle, Pityophthorus juglandis, and an associated fungus, Geosmithia morbida. TCD was first detected in the eastern United States in 2010. Eastern black walnut trees (Juglans nigra) are highly susceptible to TCD and are often killed as a result of infection, making it a serious threat to forest ecosystems and the forestry industry in the United States.

Primary activities of this project will be to investigate the ability of the TCD pathogen and vector to colonize and persist in cut logs, and to evaluate industry practices and fumigation treatment schedules for efficacy in eliminating both causal organisms from walnut logs and lumber. Researchers will also collaborate with industry groups and state regulatory officials to implement a pest risk mitigation program that will facilitate safe movement of walnut material.

EFETAC'S ROLE: This project is supported by Eastern Threat Center funding.

STATUS: Completed

PROGRESS: Researchers are completing post-treatment infestation assessment and a second trial of fumigation experiments. Experiments assessing the colonization habits of the walnut twig beetle on young, small diameter walnuts (nursery stock), naturally seasoned logs, and on samples treated with various insecticides are underway. A second trial of a post-treatment exposure experiment is in progress. Current results have been presented at the national Entomological Society of America meeting, the Second Annual Conference on Thousand Cankers Disease and Emerald Ash Borer in the Eastern United States, the Third Annual Conference on Thousand Cankers Disease and Emerald Ash in the Eastern United States, the ESA Southeastern Branch Meeting, the Southern Forest Insect Workshop Conference meeting, the Entomological Society of America meeting, and the USDA Invasive Species Forum.

A.E. Mayfield III, S.W. Fraedrich, A. Taylor, P. Merten, and S.W. Myers. 2014. Efficacy of heat treatment for the thousand cankers disease vector and pathogen in small black walnut logs. Journal of Economic Entomology 107(1):174-184.


"Slowing the Spread of Thousand Cankers Disease" (related article from CompassLive)

Paul Merten, USDA Forest Service Forest Health Protection (Southern Region), or 828-257-4845

Updated June 2015

Document Actions
Personal tools

For the latest up-to-date ag webinars on all things agriculture, visit the Agriculture Webinars Portal