Thousand Cankers Disease (Pityophthorus Juglandis) (Geosmithia Morbida )

Total Page:16

File Type:pdf, Size:1020Kb

Thousand Cankers Disease (Pityophthorus Juglandis) (Geosmithia Morbida ) Thousand Cankers Disease (Pityophthorus juglandis) (Geosmithia morbida ) Why we care: Thousand cankers disease (TCD) involves an insect native to the southwestern U.S. and a newly identified pathogen. It is a relatively new concern for black walnut trees. When tiny walnut twig beetles feed on tree branches, they introduce a fungal pathogen that causes TCD in live trees. The pathogen kills small areas of tissue, resulting in cankers. As more cankers form, branches die and over time, the entire tree succumbs. What is at risk? Michigan’s forests are home to approximately 8.5 million black walnut trees with an economic value of more the $86 million and ecological value as a food source for birds, mammals and other wildlife. There are also more than 80 walnut growers in Michigan with approximately 4,000 trees in nut production. The threat: Black walnut trees in many western states, and in Tennessee and Pennsylvania, are dying from TCD. The beetle and fungus can be transported into new areas in walnut logs, firewood and staves used for woodworking. Black walnut is a valuable timber species and important for wildlife. What could happen in Michigan? An effective control for TCD has not been identified. A high proportion of black walnut trees will likely die if TCD becomes established in Michigan. What can you do? If black walnut trees have wilting leaves or dying branches during the summer, check the tree carefully. If there is no obvious cause of the problem, such as a broken branch, note the location of the suspect tree and report it. Identifying the tiny walnut twig beetles and confirming the presence of TCD requires specialized expertise. Tiny adult walnut twig beetles vector TCD Exit holes of walnut twig beetle Whitney Cranshaw, Col State University Whitney Cranshaw, Col State University Email: [email protected] Phone: MDARD Customer Service Center (800) 292-3939 Midwest Invasive Species Information Network : www.misin.msu.edu Learn more: www.michigan.gov/exoticpests and www.thousandcankers.com This information was derived in part from Michigan State University bulletin “EXOTIC FOREST PESTS: Let’s keep them out of Michigan”, May 2013. .
Recommended publications
  • Thousand Cankers Disease
    Species Brief 5.6 What Is in Your Firewood? Thousand Cankers Disease Pest and Target Species Identification and Symptoms Thousand cankers disease (TCD) is caused The walnut twig beetle is approximately one- by the interaction between the walnut twig sixteenth of an inch long, and yellowish brown beetle, Pityophthorus juglandis (Coleoptera: to dark brown in color (Figure 1). A black walnut Curculionidae: Scolytinae), and a fungus, tree can be infected with TCD for many years Geosmithia morbida. The twig beetle is the only before showing symptoms. Not easily detected, known vector of this fungus, which can attack this insect bores into the host tree, creating the eastern species of the black walnut. The galleries (tunnel-like paths) underneath the black walnut has little to no resistance to the bark (Figure 2). The beetle carries a harmful disease. fungus on its body that spreads, causing can- kers to form in these galleries (Figure 3). The cankers expand and combine to girdle infected Range branches, disrupting the flow of water and The walnut twig beetle is native to the western nutrients. The leaves will yellow, wilt rap- United States and Mexico. Geosmithia morbida idly, and turn brown. Stem dieback or branch is also believed to be native to southwestern mortality occurs in the crown. Numerous tiny North America. This insect and fungus com- entrance and exit holes created by adult beetles plex was first identified east of the Mississippi are noticeable on dead and dying branches. Tree River in Tennessee in 2010. By the end of 2011 it mortality typically occurs approximately three had been found in Virginia and Pennsylvania.
    [Show full text]
  • Walnut Thousand Cankers Disease Alert
    Walnut Thousand Cankers Disease Alert Mary Ann Hansen1 and Elizabeth Bush1, Extension Plant Pathologists Eric Day1, Extension Entomologist Gary Griffin1, Forest Pathologist Norm Dart2, State Plant Pathologist 1Virginia Tech, 2Virginia Department of Agriculture and Consumer Services First occurrence of Thousand Cankers Disease of Black Walnut (Juglans nigra) in Virginia: On June 24th, 2011, the first case of thousand cankers disease of black walnut was found in two trees with severe epicormic branching on the lower trunk and advanced decline in Chesterfield County, Virginia. Presence of the vector and pathogen associated with this disease, the walnut twig beetle (Pityophthorus juglandis) and the fungus Geosmithia morbida, was confirmed in the samples. This is the first report of thousand cankers disease of black walnut in Virginia. The Virginia Department of Agriculture and Consumer Services (VDACS) is conducting a delimiting survey to determine the extent of the infestation surrounding the positive find. Initial delimiting survey work has found additional trees with thousand cankers disease in Chesterfield and Henrico Counties. The first report of thousand cankers disease of black walnut east of the Mississippi River (http://news.tennesseeanytime.org/node/5684) was previously reported when the Tennessee Department of Agriculture announced the occurrence of the disease in black walnut trees in Knox County, Tennessee in August 2010. Although this lethal disease has been present in parts of the western U. S. for at least a decade, it had not previously been reported east of the Mississippi River in the native range of the black walnut. The presence of this devastating disease in the southeastern U.
    [Show full text]
  • What Ever Happened to Thousand Cankers Disease?
    From The Forestry Source, June 2019. © 2019, The Society of American Foresters What Ever Happened to Thousand Cankers Disease? By Jackson Landers The first case of thousand cankers disease in the US were reported in 2001 in New Mexico. A fungus, Geosmithia morbida, was carried by some tiny walnut twig beetles into a walnut tree, where they reproduced and chewed tunnels. As the beetles spread through the tree, small cankers appeared beneath the bark like chicken pox. The sheer number of cankers overwhelmed the walnut tree as summer heated up, resulting in its Evidence of thousand cankers disease (Geosmithia death and the start of a disease that many morbida) on black walnut. Photo: Elizabeth Bush, researchers warned could wipe out North Virginia Polytechnic Institute and State University, Bugwood.org. American walnuts. Rifle manufacturers snapped up blanks for gunstocks, fearing the supply for their preferred material would disappear. species and that this was the same sort of Economists projected massive potential losses. invasive dynamic witnessed with the gypsy Eighteen years later, a lot of trees have died, but moth and, more recently, with the emerald ash the walnut apocalypse clearly has not come to borer. A recent paper in PLOS One by scientists pass as projected. According to the USDA’s from Colorado State University, Purdue Animal and Plant Health Inspection Service, University, and the US Forest Service states that walnut mortality has occurred in the West in G. morbida is native to the US, as shown by the Arizona, California, Colorado, Idaho, New robust genetic diversity found in the researchers’ Mexico, Oregon, Washington, and Utah, and as samples (see tinyurl.com/y6jvcyzq).
    [Show full text]
  • Restrictions on Moving Walnut Wood
    Black Walnut in Nebraska Thousand Cankers Disease Nebraska Forest Service Information Black walnut is native to the eastern part of Nebraska where it is commonly found along Black walnut is highly susceptible. English river and stream walnut, butternut and other walnut species Restrictions on corridors. The tree show varying degrees of susceptibility. is also widely Moving Walnut Wood planted across the Pecan and hickories are resistant. state for nut and Symptoms include yellowing foliage timber production, followed by brown wilted foliage, branch for wildlife habitat, dieback and tree death. and in certain Tree death occurs 2-3 years after initial community and symptoms appear. rural landscapes where a tough, Trees may be infected for many years drought-tolerant without visible symptoms. tree is needed. No effective chemical controls are known. TenSilver fordrangerforum.com Nebraska Black Walnut Facts For more information contact: 1.5 million trees Nebraska Department of Agriculture What you need to know 301 Centennial Mall South about 40 million board feet of merchantable wood P.O. Box 94756 • Lincoln, NE 68509 www.agr.ne.state.us (value: $40-80 million) Nebraska’s Nebraska Forest Service 1 million board feet harvested annually Forestry Hall, University of Nebraska Walnut Quarantine (value to state’s economy: $3.5 million) P.O. Box 830815 • Lincoln, NE 68583 www.nfs.unl.edu 4,000 commercial nut-bearing trees The movement of walnut wood into 70,000 pounds of nuts produced annually Nebraska from other states is restricted by (value to state’s economy: $1.2 million) Laurie Stepanek Nebraska Forest Service law. Walnut logs, firewood, green lumber, woodchips and nursery trees are among the walnut products included in this quarantine.
    [Show full text]
  • Butternut Canker and Thousand Cankers Disease
    United States Department of Agriculture US FOREST SERVICE NORTHERN RESEARCH STATION Research Review Two Fungal Diseases Spreading and Endangering Walnut Species: Butternut Canker and Thousand Cankers Disease Invasive fungal diseases and insects are assaulting hardwood tree species in our eastern forests. Although the insects receive more attention (they are more visible after all), scientists, foresters, and environmentalists are concerned that invasive fungi are endangering many hardwoods, with fungus-caused canker diseases the most destructive. Trees that produce mast—beechnuts, butternuts, walnuts, and acorns, which are food sources for many animals—are especially at risk. The most tragic example is the American chestnut, once the “queen of the eastern forests,” which has essentially been extirpated in the wild in its native range because of the canker disease chestnut blight. Cankers are localized areas of fungal infection of tree bark and cambium on branches and stems. Numerous infections and subsequent coalescing of cankers will kill trees. Butternut canker and thousand cankers disease of black walnut are cankers affecting eastern hardwoods. Since its discovery in 1967, butternut canker has established itself throughout the native range of butternut in the East, killing up to 90% of the trees in some states. Since 1990, Northern Research Station (NRS) scientists have focused their attention on conservation of butternut and the search for disease resistance in this species. The discovery of thousand cankers disease (TCD) in Colorado in 2007 and its subsequent discovery in the eastern United States have led to predictions of disastrous losses of eastern black walnut trees. NRS scientists and university colleagues are investigating how the insect-pathogen complex causing this disease may build and spread within the East and assessing what resistance exists in black walnut to both the pathogen and the insect pest.
    [Show full text]
  • Questions and Answers About Thousand Cankers Disease of Walnut
    Questions and Answers about Thousand Cankers Disease of Walnut What is thousand cankers disease of walnut? This is a newly recognized disease (2008) of certain walnut species (Juglans) caused by a fungus (Geosmithia ‘morbida’) that is vectored by a bark beetle (walnut twig beetle). Thousand cankers disease has produced widespread death of walnuts in many western states during the past decade. Recently (July 2010) it was discovered to have also been killing black walnut in the Knoxville, TN area. Is thousand cankers disease a problem confined to the western United States? No. Observations of the recently discovered infestation in Tennessee demonstrate that this disease will be a serious problem in urban and natural forests of the eastern US. There may be some regional differences in the progress of the disease and in symptoms development but the walnut twig beetle and Geosmithia ‘morbida’ appear to be well adapted to colonizing black walnuts (Juglans nigra) in the eastern United States. It appears that ultimately thousand cankers disease can be lethal to susceptible host trees where ever it becomes established. What are symptoms of the disease? A recently identified Geosmithia fungus kills an area under the bark in the twigs and branches where it is introduced when the walnut twig beetle tunnels into the limb. These dead areas are called cankers and numerous cankers are formed when the walnut twig beetles are abundant. These cankers coalesce to girdle twigs and branches, restricting movement of nutrients and interfering with production and storage of energy. (The cankers rarely show any of the external symptoms that are associated with most canker- producing fungi that affect trees.
    [Show full text]
  • Thousand Cankers Disease of Black Walnut
    UI Extension Forestry Information Series II Insects and Diseases No. 14 Thousand Cankers Disease on Black Walnut Yvonne Barkley This story begins in the summer of 2005. A land- Samples were collected and brought back to the owner in Emmett, ID reported black walnut (Jug- University of Idaho for identifi cation of the insect lans nigra) trees dying. The tree would look fi ne involved. Dr. Stephen Cook, University of Idaho and until the hot weather hit, and then the foliage Insect Ecologist, and Frank Merikel, Manager would quickly wilt and the tree would die. The of the University of Idaho William Barr Insect symptoms progresses quickly, with some trees Museum, concurred that the insect involved was dying in as little as one month. Another call came NOT Ambrosia beetles, but instead was the wal- in that same year from Meridan, ID – same thing. nut twig beetle (Pityophthorus juglandis), a native The next year, the same patterns of symptoms be- bark beetle on black walnut in New Mexico and gan to be reported in Boise. Initially, the common Arizona. thought was that trees had suffered many years of drought stress and had fi nally succumbed to While searching for information on this beetle, I the lack of suffi cient moisture. But as landown- came across an article from Boulder, CO, and the ers and resource managers began to look more description and photos matched what we were closely at the affected trees they found that there seeing here exactly. I contacted Dr. Ned Tisserat, were large numbers of very small holes in the Plant Pathologist at Colorado State University, bark, which were initially thought to be Ambro- and the story he told me was the same as ours.
    [Show full text]
  • USDA Thousand Cankers Disease Pest Alert
    United States Department of Agriculture Forest Service Northeastern Area State and Private Forestry NA–PR–02–10 Revised February 2013 Thousand Cankers Disease Dieback and mortality of eastern black walnut (Juglans nigra) in several Western States have become more common and severe during the last decade. A tiny bark beetle is creating numerous galleries beneath the bark of affected branches and the main stem, resulting in fungal infection and canker formation. The large numbers of cankers associated with dead branches and the stem suggest the disease’s name—thousand cankers disease. The principal agents involved in this disease are a newly Figure 1. Thousand cankers disease occurs in nine Western and identified fungusGeosmithia ( morbida) and the walnut twig five Eastern States (shaded gray); the year in which the disease was beetle (Pityophthorus juglandis). Both the fungus and the confirmed is noted. Since 2010, TCD has been confirmed in PA, TN, beetle only occur on walnut species and on a closely related and VA, whereas the beetle alone and the pathogen alone have tree called wingnut (Pterocarya sp.). Infested trees can die been found in OH and NC, respectively (denoted with asterisks). The map shows the native ranges of eastern black walnut (dark green) within 3 years of initial symptoms. and four western black walnut species (blue). Eastern black walnut Thousand cankers disease has been found in nine Western is widely planted in the West, but this map does not depict these States (figure 1). Since 2010, the fungus and the beetle western locations. have also been found east of the Great Plains.
    [Show full text]
  • Status and Impact of Walnut Twig Beetle in Urban Forest, Orchard, and Native Forest Ecosystems
    J. For. 117(2):152–163 BARK BEETLE SPECIAL SECTION doi: 10.1093/jofore/fvy081 Published by Oxford University Press on behalf of the Society of American Foresters 2019. Tis work is written by (a) US Government employee(s) and is in the public domain in the US. entomology Status and Impact of Walnut Twig Beetle in Urban Forest, Orchard, and Native Forest Ecosystems Steven J. Seybold, William E. Klingeman III, Stacy M. Hishinuma, Tom W. Coleman, and Andrew D. Graves The walnut twig beetle, a native phloem-boring bark beetle originating on Arizona walnut, has invaded urban, is fatal to walnut trees (Figure 2) and was frst orchard, and native forest habitats throughout the USA as well as in Italy. Although the beetle has been associated noted in the late 2000s for its involvement with dead and dying walnut trees indigenous to riparian forests of the Southwest, the primary impact appears to in the gradual deterioration and mortality of have been on the health of landscape black walnut trees in urban and peri-urban sites in western US states, and several species of black walnut in the west- in Pennsylvania, Tennessee, and Virginia. This has been refected in numbers of trees removed and tree removal ern United States (Graves et al. 2009, Flint costs. In addition, trees have been killed in the primary US Juglans germplasm repository in northern California, et al. 2010, Tisserat et al. 2011, Seybold and low, but measureable, tree mortality has occurred in some English walnut orchards in California’s Central Valley. et al. 2013b).
    [Show full text]
  • Thousand Cankers Disease: Prevention & Early Detection in The
    Thousand Cankers Disease: Prevention & Early Detection in the Upper Midwest Upper Midwest Invasive Species Conference LaCrosse, Wisconsin October 29-31, 2012 Kathryn Kromroy, Minnesota Department of Agriculture & Jennifer Juzwik, Northern Research Station, U.S. Forest Service Thousand Cankers Disease (TCD): October 2012 • Quick review • Prevention – Regulation – Outreach • Early Detection • Results to date – TCD – Other Photo by T. Choinski, Winona, MN The disease Walnut twig beetle (WTB) Pityophthorus juglandis Tunneling Entry / exit holes W. Cranshaw, Colorado State Univ., Bugwood.org W. Cranshaw, Colorado State Univ. www.forestryimages.org The disease • The walnut twig beetle introduces a fungus - W. Cranshaw, Colorado State Geosmithia morbida Univ., Bugwood.org • that kills the bark & phloem, causing cankers Ned Tisserat, Colorado State University Ned Tisserat, Colorado State University • that coalesce to girdle the branch or stem The disease Dieback & decline Death K. Kromroy, MDA. Boulder, Colorado Oct. 2011 Whitney Cranshaw, Colorado State University Hosts of Thousand Cankers Disease: Juglans Susceptibility high • Black walnut (J. nigra) • Hinds, or northern California walnut (J. hindsii) • Southern California walnut (J. californica) • Black walnut hybrids (J. nigra x J. sp.) • English walnut (J. regia) • Little walnut (J. microcarpa) • Arizona walnut (J. major) low Reports of WTB & black walnut mortality before 2009 1928: Original description of WTB in New Mexico 1959: WTB in California 1988: WTB in Utah 1990s: Walnut decline,
    [Show full text]
  • National Response Framework for Thousand Cankers Disease (TCD) on Walnut
    National Response Framework for Thousand Cankers Disease (TCD) on Walnut US Forest Service, Animal Plant Health Inspection Service, National Association of State Foresters, and the National Plant Board 2011 i | P a g e Forward Approval This framework represents a combined national effort to address Thousand Cankers Disease (TCD) on Walnut. We, the undersigned, approve this document and its intent toward better management of this emerging insect/disease complex. ii | P a g e Executive Summary Purpose A newly discovered insect/disease complex called Thousand Cankers Disease (TCD) has been identified as a potential threat to the nation’s walnut resource. This document contains information to guide state foresters, agriculture officials, and legislative staff on Thousand Cankers Disease (TCD) of walnut. It is intended to serve as a reference for land managers and government agencies currently dealing with this complex and states (as yet) not affected by TCD. It lays the foundation for prioritizing on-the-ground work, research, and resource needs. The implementation of specific activities outlined in the framework is flexible and based on the best available information at this time. Themes common to all framework elements include partnerships, collaboration, communication, and education. Success will be dependent on the ability to improve capacity, streamline procedural activities, and long-term commitment. This report outlines the US Depart- ment of Agriculture’s (USDA) and its key partner’s comprehensive framework to respond to TCD centering on five key elements: Prevention Detection/Monitoring Management Outreach/Education Research The USDA Forest Service (State and Private Forestry, Forest Health Protection) has convened a group of subject matter experts from research, state, and federal agencies to emphasize the importance of this emerging insect/disease complex, and provide a basis for protecting the nation’s walnut resource.
    [Show full text]
  • Thousand Cankers Disease of Walnut (Geosmithia Morbida)
    Published by Utah State University Extension and Utah Plant Pest Diagnostic Laboratory PLP-015pr August 2011 Thousand Cankers Disease of Walnut (Geosmithia morbida) Claudia Nischwitz, Extension Plant Pathologist • Marion Murray, IPM Project Leader What you should know • Thousand cankers disease is caused by the fungus Geosmithia morbida. • It is transmitted by the walnut twig beetle (Pityoph- thorus juglandis). • Once symptoms are visible, trees can die within 2 to 3 years. INTRODUCTION Thousand cankers is a newly recognized disease of walnuts, caused by a fungus (Geosmithia morbida) Fig. 1. Walnut twig beetle (Pityophthorus juglandis)1 that is spread by the walnut twig beetle (Pityophthorus juglandis, Fig. 1). The beetle is endemic to the native range of Arizona walnut (Arizona, New Mexico, and Chihuahua, Mexico), and was first identified in Utah in 1988. Widespread mortality of black walnut in the early 2000s in Colorado and Utah led to the discovery of the pathogen-vector complex. The name of the disease comes from the numerous necrotic lesions (cankers, Figs. 4a and b) found on the cambium of infected trees (Tisserat et al. 2009). The fungus kills black walnut trees (Fig. 2) often within 3 years of the development of the first symptoms (Cranshaw and Tisserat 2008). HOSTS Fig. 2. 400-year old black walnut killed in northern Utah Black walnut (Juglans nigra) and black walnut hybrids are very susceptible to Geosmithia. California walnuts (J. hindsii, J. californica) and Persian walnuts (J. regia) are slightly susceptible. Cankers do not seem to form on Arizona walnuts (J. major) (Cranshaw and Tisserat 2008). SYMPTOMS It may take several years of insect and fungal attack before symptoms are visible, starting with yellowing leaves and thinning tree crown.
    [Show full text]