Minnesota First Detectors

Thousand Cankers Disease

What is it?

Where is it?

Why do we care?

What should we be do about it now?

Kathleen Alexander, Boulder, CO

Minnesota First Detectors

Thousand Cankers Disease

What is it? A disease of some walnut trees that is caused by an insect and a fungus

Where is it? In western and southwestern areas of the United States

Why do we care? Because if it spreads eastward, it may threaten native eastern black walnut in several states

What should we do about it now? Be aware -

recently discovered, still many unanswered questions

Minnesota First Detectors

Juglans susceptibility - Tentative

Least Moderate Very

Arizona walnut (Juglans major)

Northern California black walnut

(J. hindsii)Eastern black walnut

(Juglans nigra) Little walnut (Juglans microcarpa)

California black walnut (Juglans californica)

English walnut (Juglans regia)

???

Butternut (Juglans cinerea)

???

Thousand Cankers Disease: What is it?

Two occur in Minnesota – J. cinerea, J. nigra

A disease of some walnut trees (Juglans species)

Minnesota First Detectors

….. caused by a tiny insect that feeds and tunnels in the inner bark of the trunk and branches

Walnut twig beetlePityophthorus juglandis

Whitney Cranshaw, Colorado State University, Bugwood.org

Tunneling

Entry / exit holes

W. Cranshaw , Colorado State Univ. www.forestryimages.org

Thousand Cankers Disease: What is it?

Minnesota First Detectors

The walnut twig beetle introduces a fungus -

Geosmithia morbida

that kills the bark and phloem, causing a canker

Ned Tisserat, Colorado State University

Whitney Cranshaw, Colorado State University, Bugwood.org

Jim LaBonte, OR Dept. Agric.

“Canker: A visible dead area, usually of limited extent, in

the cortex or bark of a plant.”(Tainter & Baker, 1996)

Thousand Cankers Disease: What is it?

Minnesota First Detectors

Cankers coalesce, eventually girdling and killing the branch or trunk

Ned Tisserat, Colorado State University

Thousand Cankers Disease: What is it?

Minnesota First Detectors

Yellowing & wilting foliage, followed by branch dieback & death may occur in susceptible species

Kathleen Alexander , City Forester, Boulder, CO Whitney Cranshaw, Colorado State University

Thousand Cankers Disease: What is it?

Minnesota First Detectors

2010

Thousand Cankers Disease: Where is it?

States in red & Tennessee

Original host, Arizona walnut Juglans major

Confirmed July 2010

Minnesota First Detectors

Black walnut dieback for 2+ years.

TCD confirmed July 2010. TCD confirmed in 4

counties. Surveys initiated in

neighboring states.

Urban settings news.tennesseeanytime.org/node/5926

1st report in native range

Knoxville, TNSource: M. Mielke NCFPW 2010

Thousand Cankers Disease: Where is it?

KY

NC

GA

VAMO

MS AL

Minnesota First Detectors

…because it threatens eastern black walnut in its native range & there is no control

Thousand Cankers Disease: Why do we care?

Minnesota First Detectors

MissouriIowa

WisconsinMinnesota

0

20,000,000

40,000,000

60,000,000

80,000,000

100,000,000

120,000,000No. Black Walnut Trees > 1” dbh on Forestland

18.5 million

41.9 million

18.5 million

41.9 million

100.9 million

Miles, P.D. Fri. Nov 05 19:16:48 CDT 2010 Forest In-ventory EVALIDator web-ap-plication version 4.01 beta.

……. black walnut in urban landscapes?

5.9 million

Thousand Cankers Disease: Why do we care?

Minnesota First Detectors

United States 1.9% total hardwoods available commercially net volume growing stock valued at > $500 billion exports to 67 countries annual average value of export is $325 million

Minnesota 1-2 million board feet harvested annually 0.1% of volume of all wood harvested $3 million = 5% of $60 million total stumpage value

for all wood harvested

Thousand Cankers Disease: Why do we care?Impacts on wood products industries

Minnesota First Detectors

Ecologic Harder to measure Nuts as food for wildlife – squirrels,

beavers, red-bellied woodpeckers Important species of riparian corridors Bark used for medicine, dye

Social Culture around walnuts for food

Thousand Cankers Disease: Why do we care?Other impacts

Minnesota First Detectors

National Response Framework for Thousand Cankers Disease (TCD) on Walnut

Prepared by:TCD-Technical Working Group

To coordinate response among government, non-government & private stakeholders

Thousand Cankers Disease: What should we do?

Minnesota First Detectors

Pathway Estimated approach rate USDA APHIS Pathway Assessment 2009

Timber Low: Production low in west; little shipped from west to east

Firewood Low to moderate: Firewood distributors, long distance campers

Wood packing material (WPM)

Low to moderate: WPM with most domestically shipped commodities, 1.2 billion pallets in circulation

Nursery stock Low: No reports of infested nursery stock

Scion wood Low: Revised breeding programs in west to prevent spread

Natural spread Low: Walnut twig beetle flies 1-2 miles; carried by wind

Minimize introduction risk potential pathways?

Thousand Cankers Disease: What should we do?PREVENTION

Minnesota First Detectors

Regulation

Outreach

Early detection

Thousand Cankers Disease: What should we do?

Tools for prevention

Minnesota First Detectors

Thousand Cankers Disease: What should we do?

Who regulates? Infested western states? No

APHIS?

Not at this time

Eastern states?

Yes

Regulation

Minnesota First Detectors

Source: E.Borchardt, MN Dept. Agric.

Exterior quarantines

Exterior quarantines

Interior quarantine

Thousand Cankers Disease: Regulation

State Quarantines

?

Minnesota First Detectors

Newsletter articles, websites Telephone, email, visits

Presentations First Detector networkPartner organizationsMill ownersLoggers LandownersTree care companiesNurseries

Photos courtesy of Mike Greenheck, Forest Field Day , Gorman Creek Farm, Kellogg, MN, October 2010

Thousand Cankers Disease: What should we do?

Outreach

Minnesota First Detectors

TCD tree takedown workshops

First detector training

Visual surveys & sampling from suspect trees

Site solicitation efforts

Thousand Cankers Disease: What should we do?

Early Detection

Minnesota First Detectors

Early Detection: Does your black walnut have TCD?

Early symptoms (late June to late August)

Area of thinning crownYellow or wilting leaves

Leaves smaller than healthy leaves

Attached brown leaves

Minnesota First Detectors

Rapid wilting

Early Detection: Does your black walnut have TCD?

Actively declining crown symptoms

Little live crown on trees affected previous season

Limbs die in 1 season

Cankers on branch below wilting foliage

Minnesota First Detectors

Early Detection: Does your black walnut have TCD?

Late symptomsMany tiny holes on branches >1.5 inches

Galleries and meandering tunnels

Large dead areas on branches & stems

Small cankers in inner bark if scrape away outer bark

Minnesota First Detectors

Early Detection: Does your black walnut have TCD?

What else may be confused with Thousand Cankers Disease?

Anthracnose

Fusarium cankers -similar decline Other beetles

Hail injury, storm damage

Squirrel girdling of branches

Nectria cankers

Minnesota First Detectors

POTENTIAL TREES FOR 2010 THOUSAND CANKERS DISEASE TARGETED SURVEY (Minnesota)

Dieback in Black Walnut Observed between mid-June and late August 2010

Please return by mail, email or fax to one of the following locations: Jennifer Juzwik / Mike Ostry/Paul Castillo Kathy KromroyUSDA Forest Service, 1561 Lindig St. Minnesota Dept. of Agric., Plant Protection DivisionSt. Paul, MN 55108 625 Robert Street North, St. Paul, MN 55155-2538E-mail: jjuzwik@fs.fed.us or mostry@fs.fed.us Kathryn.Kromroy@state.mn.us Facsimile: (651) 649-5040 Facsimile: (651) 201-6108Telephone: (651) 649-5114 (JJ) and (651) 649-5113 (MO) Telephone: (651) 201-6343

ORPlease enter information on-line using the US Forest Service, NA S&PF “survey monkey” at: http://www.surveymonkey.com/s/thousandcankers

SUBMITTER’s CONTACT INFORMATION: Date of submission:

LANDOWNER OR LAND MANAGER INFORMATION:

JUGLANDACEAE INFORMATION: Please fill in the section with as much information as you haveDESCRIPTION OF THE SITUATION

Thousand Cankers Disease: What should we do?

Targeted survey for thousand cankers disease of walnut in Minnesota: USDA Forest Service Northern Research Station and the Minnesota

Department of Agriculture

Minnesota First Detectors

Acknowledgements

Jenny Juzwik, Mike Ostry, Paul Castillo. USFS Northern Research Station

Manfred Mielke. USFS State & Private Forestry

Keith Jacobsen, Lance Sorenson, Don Deckard, MN DNR

Mike Greenheck, grower, Gorman Creek Farms, Kellogg MN

Mel Baughman, Angie Gupta, UM Extension