Thousand Cankers Black Walnut Disease | National Invasive Species Information Center

Thousand Cankers Disease - Walnut twig galleries and cankers in branch of hybrid walnut; associated with walnut trig beetle Ned Tisserat, Colorado State University

Scientific Name:

Geosmithia morbida (Kolařík et al. 2011)

Common Name:

Thousand cankers black walnut disease (TCD)

Native To:

Disease was first detected in the Western U.S.; the disease vector, the walnut twig beetle, is native to the southwestern U.S. and Mexico (Utley et al. 2013)

Date of U.S. Introduction:

First observed in the 1990s, but not recognized until 2008 (Utley et al. 2013)

Means of Introduction:

Unknown, but possibly through the transportation of logs and firewood (Randolph et al. 2013)

Impact:

Fungal disease of walnut trees (Juglans spp.), particularly the black walnut (Juglans nigra), that is usually lethal within a few years; disease is transmitted by the walnut twig beetle, Pityophthorus juglandis (Tisserat et al. 2009)

Current U.S. Distribution:

Widespread throughout the Western U.S.; first detected in the Eastern U.S. in Aug 2010

Spotlights

Countering Thousand Cankers Disease (Sep 5, 2019)

USDA. FS. Southern Research Station. CompassLive.

In recent decades, thousand cankers disease has become a concern for walnut growers and hardwood forest managers in the United States. A variety of measures have been investigated or developed to counter the disease. A study led by USDA Forest Service research entomologist Albert Mayfield and former University of Tennessee graduate student Jackson Audley looked at one measure: quarantine treatments. In an effort to stop the spread of the walnut twig beetle, certain states have prohibited the movement of regulated articles, including kiln-dried walnut lumber that still has its bark. The scientists investigated the risk of that type of lumber becoming colonized during movement to evaluate whether regulation of that product is necessary. Their paper was published in the Journal of Economic Entomology.

Distribution / Maps / Survey Status

Early Detection & Distribution Mapping System (EDDMapS) - Thousand Cankers Disease

University of Georgia. Center for Invasive Species and Ecosystem Health.

Provides state, county, point and GIS data. Maps can be downloaded and shared.

Images

Google Images - Thousand Cankers Black Walnut Disease

Google.

Invasive.org - Thousand Cankers Black Walnut Disease

University of Georgia. Center for Invasive Species and Ecosystem Health.

Videos

YouTube - Outsmart Invasive Species Project: Thousand Cankers Disease ID

Google. YouTube; University of Massachusetts - Amherst.

YouTube - Tree Diseases (includes Thousands Cankers)

Google. YouTube; University of Tennessee Extension (Knoxville County).

Selected Resources

The section below contains highly relevant resources for this species, organized by source. Or, to display all related content view all resources for Thousand Cankers Black Walnut Disease.

Partnership

EPPO Global Database - Geosmithia morbida

European and Mediterranean Plant Protection Organization.

First Detector Program - Thousand Cankers

National Plant Diagnostic Network.

You can become a more effective First Detector by familiarizing yourself with invasive target pests and pathogens known to exist in the U.S. If you think you have encountered one of the species or disease complexes listed, report its presence.

Gallery of Pests - Thousand Canker Disease

Nature Conservancy. Don't Move Firewood.

Invaders Factsheet: Thousand Cankers Disease

Ontario's Invading Species Awareness Program (Canada).

National Pest Alert: Thousand Cankers Disease of Walnut

North Central Integrated Pest Management Center.

See also: Pest Alerts for more resources

Phytosanitary Alert System - Geosmithia spp. and Pityophthorus juglandis

North American Plant Protection Organization.

Thousand Cankers Disease

Thousand Cankers Disease.

Federal Government

Pest Alert: Thousand Cankers Disease (Feb 2013)

USDA. FS. Northeastern Area State and Private Forestry.

Forest Disturbance Processes - Thousand Cankers Disease

USDA. FS. Northern Research Station.

Plant Pest and Disease Program: Plant Disease - Thousand Cankers Disease

USDA. Animal and Plant Health Inspection Service.

State and Local Government

Thousand Cankers Disease - 2010 Georgia Update (Sep 2010) (PDF | 889 KB)

Georgia Forestry Commission.

See also: Forest Health - Diseases for more resources

Invasive Tree Pests - Thousand Cankers Disease

Missouri Department of Conservation.

See also: For more information about Invasive Tree Pests (insects and diseases) that are not native to Missouri

Plant Diseases - Thousand Cankers Disease of Walnut

Minnesota Department of Agriculture.

Plant Pests, Diseases and Quarantines - Thousand Cankers Disease

Tennessee Department of Agriculture.

Thousand Cankers Disease (TCD) poses a serious problem to the health of the black walnut tree. Tennessee Department of Agriculture officials urge area residents and visitors to help prevent the spread of TCD:

Don't transport firewood, even within Tennessee.
Don't buy or move firewood from outside the state.
Watch for signs of infestation in your walnut trees.

If you suspect your walnut tree could be infected with TCD, refer to the TCD Symptoms Checklist to alert state plant and forestry officials, or call TDA's Consumer and Industry Services Division at 1-800-628-2631.

Plant Protection and Weed Control - Thousand Cankers Disease of Walnut

Kansas Department of Agriculture.

Thousand Cankers poses a serious threat to the health of black walnut trees. The Kansas Department of Agriculture, Kansas Forest Service and K-State Research and Extension need your help to help stop the introduction, and to limit the spread, of this disease in Kansas. We are deeply concerned that if it reaches the native range of black walnuts in central and eastern Kansas, we may lose this tree in our urban and native forests.

Regulatory & Scientific Information: Thousand Cankers Disease

Indiana Department of Natural Resources. Entomology and Plant Pathology.

Walnut Twig Beetle and Thousand Cankers Disease

Maryland Department of Agriculture.

Thousand cankers disease (TCD) is a disease complex native to the western United States and primarily affects black walnut, Juglans nigra. This disease is the result of the combined activity of a fungus, Geosmithia morbida, and the walnut twig beetle WTB), Pityophthorus juglandis. On January 12, 2015, the the Maryland Secretary of Agriculture issued a quarantine order to minimize the risk of moving infested material out of the limited action area in Cecil County, and to provide confidence in Maryland walnut products moving into neighboring states from non quarantined areas. The 2015 quarantine order has been updated to include all of Baltimore City and part of Baltimore County (PDF | 1.2 MB). The new quarantine (PDF | 1.0 MB) was signed on May 1, 2019 by the Maryland Secretary of Agriculture.

Academic

Thousand Cankers Disease: A Threat to Black Walnut in Florida (Feb 2013)

University of Florida. Institute of Food and Agricultural Sciences.

Utah Pests Fact Sheet - Thousand Cankers Disease of Walnut (Aug 2011) (PDF | 1.44 MB)

Utah State University. Cooperative Extension.

See also: Landscape Ornamental Insects for more fact sheets

Thousand Cankers Disease of Black Walnut: A New Pest May Threaten Texas Walnut Trees (Feb 2010) (PDF | 1.46 MB)

Texas A&M University. Texas Forest Service.

Emerging Threats: Thousand Cankers Disease of Walnut

Kansas State University. Kansas Forest Service.

Pacific Northwest Plant Disease Management Handbook - Thousand Cankers Disease (Black Walnut Decline)

Oregon State University. Extension Service.