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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, mortality in Utah, Idaho, Oregon *2001: 1st report mortality assoc. with WTB, New Mexico 2001 – 2008: WTB, mortality in other western states *2008: Geosmithia isolated from cankers surrounding WTB galleries in declining walnuts in Colorado TCD occurrence 2009 - 2012 Nevada 2011 Pennsylvania 2011 ! Virginia ! 2011 Tennessee 2010 Original host, Arizona walnut (Juglans major) TCD threatens eastern black walnut, an important resource Iowa • 3rd largest volume black walnut in world - 979 million board feet • TCD estimated loss total $1.8 billion, $72 million/year Wisconsin • 18.5 million black walnut trees • Annually export > $4 million in products Minnesota • 6 million black walnut trees on forestland & almost 300,000 in urban areas (2010 MN DNR Rapid Assessment data). • Annual state harvest is 1-2 million board feet; 4% of $75 million total stumpage value for all wood harvested • 40+ mills in Minnesota use walnut; 12% imported (WI, IA) bark on What should we do? Thousand Cankers Disease Prevention: Regulation & Outreach What are the pathways? With some ideas about pathways, target the origin, destination and “in-between” with outreach and regulation. Prevention: Outreach . Newsletters, websites . Telephone, email, visits . Presentations . Surveys TO .Partner organizations .Mill owners, loggers .Landowners .Tree care companies .Nurseries Photos courtesy of Mike Greenheck, Forest Field Day, Gorman Creek Farm, Kellogg, MN, October 2010 Regulation: Quarantines . What is a quarantine? . Series of rules regulating the movement of certain articles to prevent the spread of pests that threaten a resource . Who can establish a quarantine? . Agencies with the authority to protect the threatened resources – varies by state . What are the different kinds of quarantines? . Federal vs. state . Interior vs. exterior Regulation: Quarantines Who is regulating for TCD? Infested western states? No APHIS? No Eastern states? Yes State Quarantines Regulations to prevent spread of TCD: State exterior quarantines Some key elements: State Minnesota Wisconsin Iowa Regulatory Dept. of Dept. of Agriculture, Dept. of Agency Agriculture Trade & Consumer Agriculture (MDA) Protection (DATCP) (IDA) Effective date (2/3/2011) 8/1/2011 No exterior of exterior 8/8/2011 quarantine at quarantine this time State exterior quarantines: Minnesota, Wisconsin, Michigan State Minnesota Regulated Walnut twig beetle; articles G. morbida; all plants, plant parts of genus Juglans, including but not limited to: logs, green lumber, nursery stock, scion wood, bud wood, chips, mulch, stumps, roots, branches, packaging material; all hardwood firewood; (WI – firewood of all species) Other Exempt Nuts, nutmeats, hulls; articles Processed lumber + 100% bark free & kiln dried with squared edges; Finished wood products without bark, including walnut furniture, musical instruments & gunstocks. Sale &/or movement of regulated articles into state: If originate in or transit Prohibited unless importer has compliance agreement through a state or other with MDA and articles have a phytosanitary certificate area known to have TCD from originating state verifying that material meets conditions of the compliance agreement. (MI – PROHIBITED) If originate in other areas Must provide proof of harvest location by state (WI - ?) Special exemptions May be moved into state for research purposes with written approval from Commissioner Pathway surprises Juglans seedlings from western state Juglans logs at rail yard P. Haiker, MDA P. Ahlen, MDA http://www.woodweb.com/cgibin/ forums/vawp.pl?read=531138 Juglans raw wood: burls for wood hobbyists (PA, OH) T. Seeland, MDA. Davis, Nov. 2011 “All of our reclaimed wood slabs are salvaged from urban or rural residences from hazardous or unwanted Juglans products made trees. We do everything from harvesting and from killed walnut transporting the trees (from California and other parts of the world).” Thousand Cankers Disease: Early Detection Identify high risk sites: Rail yards, mills, those with reported walnut dieback or decline Visual survey: assess individual tree condition and look for signs and symptoms of TCD Trapping: Use lure specific for walnut twig beetle in Lindgren funnel traps S.Seybold, USFS Early Detection: Visual survey . Wilting leaves . Attached brown leaves . Small leaves Early Detection: Trapping with WTB lure TCD Early Detection in Minnesota: 2011 Visual Survey: MDA & USFS • 109 sites - urban, industrial & rural • 2548 black walnut trees • 5 (<1%) suspect & sampled • None with WTB or TCD TCD Early Detection in Minnesota: 2012 R. Mayeda, 2012 Willmar MN 2012 Visual & Trapping Survey: MDA • 41 sites, urban, industrial & rural) • 885 black walnut trees • 11 (1%) suspect & sampled • Traps at 3 sites, 3 per site • ?? with WTB or TCD TCD Early Detection in Iowa: 2011 Visual Survey: Tivon Feely, IA DNR • 204 sites: 64 urban, 140 rural • 850 black walnut trees • 13 (<2%) suspect & sampled • NO WTB or TCD TCD Early Detection in Iowa: 2012 2012 Trapping Survey: Iowa DNR, Tivon Feeley • 438 traps, all with beetles, 1 – 68 beetles trap • Several different beetles, many identified • 343 (78%) with ambrosia or Pityophthorus species • No WTB TCD Early Detection in Wisconsin: 2011 Visual Survey: Mark Guthmiller, WI DNR • 28 sites – natural (state parks) & plantation stands • Varying levels of dieback & decline • Branch sampling - 44 samples (2 per tree) 2011 TCD Early Detection in Wisconsin: 2011 Visual Survey Results • Observed late bud break & leaf expansion, branch flagging & early yellowing, dieback, sapsucker injury, epicormic branching • None with WTB or TCD • Other pests & diseases observed in “declining” trees & stands • Predisposing: sites, soils, phytoplasma diseases (?) • Inciting: cold injury • Contributing: ambrosia beetles, buprestid beetles, walnut scale, other canker fungi (Fusarium, Nectria) Early Detection in Wisconsin: 2012 Trapping Surveys: Rebecca Gray, WI DATCP • 15 mills • 2 traps per mill • To date - NO WTB WI DNR, M. Guthmiller, Renee Pinski • 21 sites • 2 traps/site Early Detection in Wisconsin: 2012 WI DNR, more results from sites in southern Wisconsin Phytoplasma tests • 4 sites positive (Agdia testing,2011 & 2012), 1 from butternut, 3 from black walnut. Branch Rearing for Agrilus and WTB • 6 sites with decline from 2011 were branch sampled and put in rearing containers. • No suspect WTB were recovered. • Agrilus beetles (3 spp.) reared from 5 of 6 sites; all from dry recent dead branch material vs branch material with green cambium. • Species previously documented on walnut, may play secondary role in decline. Walnut Decline Surveys • 6 sites with decline in 2011 surveyed in 2012; all negative for WTB based on branch peeling. To date, no WTB or TCD What’s next? • Continue outreach: target other audiences • Continue regulation: work with industry to promote business while protecting resource • Continue survey: visual, trapping with pheromone, other trapping (largely with Farm Bill support) Thanks to: Tivon Feeley, Forest Health Program Leader Iowa Department of Natural Resources, Des Moines, IA 50319-0034 Mark Guthmiller, Forest Health Specialist-Southern Region Wisconsin Department of Natural Resources South Central Region, Fitchburg, WI 53711 Rebecca H. Gray, Environmental Enforcement Specialist Wisconsin Dept. of Agriculture, Trade & Consumer Protection Madison, WI 53718 APHIS PPQ for funding Bob Koch, Minnesota Department of Agriculture Paul Castillo, U.S. Forest Service, Northern Research Station, St. Paul, MN Mike Greenheck, Gorman Creek Farms, Kellogg, MN Minnesota Department of Natural Resources .
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  • 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.
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