Thousand Cankers Disease (TCD)

transcript

Minnesota First Detectors

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; in Tennessee (2010), Virginia, Pennsylvania (2011)

Why is it important? Because as it spreads eastward, it threatens native eastern black walnut

What are we doing? Prevention, early detection; management

Declining black walnutBoulder, Colorado Oct. 2011

K.Kromroy

Thousand Cankers Disease: What is it?

Two Juglans occur in Minnesota

A disease of walnut trees (Juglans species)…

www.plantcare.com/.../black-walnut-2127.aspx www.tree-pictures.com/butternut_tree_photos.html

Eastern black walnut (Juglans nigra): Very susceptible

Butternut (Juglans cinerea): Jan. 2012 , Eugene OR - 1st report of natural infection

Walnut twig beetle (WTB)Pityophthorus juglandis

Whitney Cranshaw, Colorado State University, Bugwood.org

TunnelingEntry / exit holes

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

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

The walnut twig beetle introduces a fungus - Geosmithia morbida

that kills the bark and phloem, causing a canker

Ned Tisserat, Colorado State University

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

Ned Tisserat, Colorado State University

Cankers grow together, eventually girdling and killing the branch or trunk

Whitney Cranshaw, Colorado State University

Yellowing & wilting foliage, branch dieback; death in susceptible species

K. Kromroy, MDA. Boulder, Colorado Oct. 2011

History of WTB and TCD Prior to 2003

Original description of WTB, New Mexico

1928 Early 1990’s

2001 2003

Reports of black walnut decline & mortality in

Oregon & Utah

Report of black walnut mortality, northern New

Mexico; WTB associated.

Reports of black walnut decline & mortality in

Boulder & Denver, Colorado

Thousand Cankers Disease: Where is it now?

Original host: Arizona walnut

TCD is in all the red states

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

Why is it important?

MissouriIowa

WisconsinMinnesota

20,000,000

40,000,000

60,000,000

80,000,000

100,000,000

120,000,000

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 Inventory EVALIDator web-application version 4.01 beta.

5.9 million

Number of Black Walnut Trees > 1” dbh on Forestland

Black Walnut in Minnesota

5.9 million trees on forestland; Winona, Wabasha, Fillmore Counties > 1 million black walnut each

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

Almost 300,000 black walnut in urban areas (2010 MN DNR Rapid Assessment data).

Black Walnut Through Minnesota – hundreds of logs each year

P. Ahlen, MDA

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

red-bellied woodpeckers• Important species of riparian corridors

Social• Culture around walnuts for food• Bark used for medicine, dye

Other Values of Black Walnut

To our knowledge, TCD is still absent from Minnesota

Choinski, 9/2011

PREVENTION Education Regulation

Thousand Cankers Disease: What are we doing?

EARLY DETECTION

Prevention: What are the pathways?PATHWAY ESTIMATED APPROACH RATE

Newton, L. & Fowler, G. 2009. Pathway Assessment: Geosmithia sp. and Pityophthorus juglandis Blackman movement from the western into the

eastern United States. USDA APHIS Rev. 1:10.19.2009. 50 pgs.

Timber Low; little timber shipped from west to east

Firewood Low - moderate; firewood distributors, long distance campers

Wood packing Low to moderateNursery stock Low; no reports of infested nursery plants

Scion wood Low; programs in west revised to prevent spreadNatural spread Low; beetle flies 1-2 miles

………..Wood for hobbyists

ESTIMATED APPROACH RATE: ???? Internet sales; mail order companies; friends/acquaintances

WTB spread from California to Pennsylvania

http://www.furnituredesignidea.com/3729/cool-wooden-furniture-heartwood-design-furniturehttp://www.primocraft.com/Bar-

Features/Walnut-Burl-Inlay.html

http://www.woodweb.com/cgibin/forums/vawp.pl?read=531138

Black walnut logs, slabs, burls with bark attached.

T. Seeland, MDA. Davis, Nov. 2011

Newsletters, websites Telephone, email, visits Presentations

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

Education

Regulation

Who regulates?

Infested western states - No APHIS - No

Eastern states - Yes

Thousand Cankers Disease: Regulation

Thousand cankers disease occurs Black walnut native range Exterior quarantine, terms vary by state Interior quarantine, by county

2 counties added

Early Detection

2011 • More than 2500 walnut trees visually assessed in

urban, rural and industrial communities • 5 suspect trees sampled and examined in lab• NO TCD

2012 • Visual assessment of walnut trees at or near

mills that use walnut• Traps with walnut twig beetle lure hung at 2 sites• Data analyses in progress

2013 • Farm bill funding for TCD surveys in MN and 16

other states• MN will hang traps at 10 high risk sites• Continue visual assessment

Early Detection: It’s here – a trap with a lure!

S.Seybold, USFS

Visual Assessment: Early symptoms

Thinning crown

Yellow or wilting leaves

Tree may be infested 7 or more years before see crown symptoms

J.Juzwik, USFS

Early symptoms

Wilting leaves

Attached brown leaves

Small leaves

J.Juzwik, USFS

Photo by T. Seeland, MDA, Denver, Colorado, June 2011

Oozing canker on Juglans nigra

Actively declining symptoms – rapid wilting

Branch cankers below wilting foliage

J.Juzwik, USFS

Top down dieback

B.Moltzan, USFS

Many tiny holes on branches >1.5 inches

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

Galleries and meandering tunnels

Small cankers in inner bark

J.Juzwik, USFS

Old cankers under bark on Juglans nigra lose their color

Photo by T. Seeland, MDA, Denver CO June 2011

Large dead areas on branches & stems

J.Juzwik, USFS

What else might be mistaken for TCD?

Anthracnose Fusarium cankerJoseph O'Brien, USDA Forest Service, Bugwood.orgJ.Juzwik, USFS

Unknown

What else might be mistaken for TCD?

Site stressPhoto by Choinski, 9/2011J.Juzwik, USFS

Other insects and their damage

Asian ambrosia beetleXyleborinus saxeseni

Insects found on girdled black walnut in Indiana & Missouri:

Ambrosia beetles – 7 species

Weevils – 5 types

Bark beetles – 2 species

80% of beetles in MO

Natasha Wright, Florida Department of Agriculture and Consumer Services, Bugwood.org

Cossoninae weevilHimatium errans

Weevil holes

Weevil tunnels?

On walnut log, St. Paul rail yard 2011

Photos by J.Juzwik, USFS

Tree removal Proper disposal

BuryBurn

Sanitation

Management

Disposal site in Boulder, Colorado October 2011, K.Kromroy, MDA

Treatments for wood: Heat, debarking, fumigation Treatments for trees: Insecticides Insects

WTB genetics, behavior, cold tolerance Other insects that may vector pathogen

Fungi Genetics, aggressiveness Other canker fungi

Variation in susceptibility/resistance of the host Role of stress in WTB attraction and in canker development Time-line of disease progression

Studies in progress – preliminary results

Management

Acknowledgements

Jenny Juzwik, Paul Castillo - USFS Northern Research Station.

Keith Jacobsen, Don Deckard, Lance Sorenson -MN DNR.

Mike Greenheck - Gorman Creek Farms, Kellogg MN.

Angie Gupta - UM Extension.

Tina Seeland, Bob Koch, Mark Abrahamson - MDA

Thousand Cankers Disease (TCD)

Documents