1. Thousand Cankers Disease in
Pennsylvania
What We Know. Where We Are Going.

2. What is Thousand Cankers Disease?
 A Juglans (sp.) tree disease caused by the combined
activities of the Walnut Twig Beetle, Pityophthorus
juglandis and the fungus Geosmithia morbida.
 When you find, Walnut Twig Beetle (WTB) you find the
fungus.
 The fungus grows and forms cankers each time the
WTB pierce the tree.
 Cankers coalesce and girdle the tree.
 Tree will begin to show signs of flagging and dieback.
 Death may ensue within 8-10 years of introduction of
TCD.

3. Walnut Twig Beetle

4. Walnut Twig Beetle
USFS
confirms WTB found in Bucks
County are genetically linked to WTB in
Chico, California.
Photo by Donna Brandt, MO

5. Geosmithia morbida
As the larvae
develops, G. morbida
is found growing with
the larvae.

6. Black Walnut
Higher
value than other hardwoods
Veneer, furniture, oils, gunstocks
Valuable for international markets
Prized by artisan woodworkers
Less than 1% PA hardwoods
Nebraska and Missouri plantation
plantings for retirement
Human/Wildlife food source

7. Cooperative Effort
Scott
Guiser, Bucks County, Extension
Educator visited the property owner,
recommended a sample
Sara May, NPDN – Penn State University
diagnosed Geosmithia morbida, Greg Hoover –
Penn State University identified Walnut Twig
Beetle
Sara May notified Coanne O’Hern, USDA and
Dana Rhodes, PDA of Thousand Cankers
Disease
PDA confirmed TCD and placed quarantine on
Bucks County

8. Property of TCD Find
10
Trees Identified with TCD Initially

9. Property of TCD Find
Property Owner is an Artisan
Woodworker. Black Walnut is the
wood of choice. Including
shipments of Walnut from CA.
The Live Edge is very important to
Artisan Woodworkers.

10. Property of TCD Find
Property owner is an Arborist
and brings downed trees to
Bucks county property.

11. Property of TCD Find
Property owner is a Firewood Distributor.
Walnut was included in the mix.

12. Counties Known To Have TCD

13. Bucks County
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Large Mulch producing facilities.
Many mulch facilities have suppliers sign statements saying “Walnut
Excluded”. This was a decision of the mulch producers.
Burn ban in many townships. Townships with bans arranged sites
for township property owners to have burnings for Walnut debris.
Much debris after Hurricane Irene and Tropical Storm Lee
Many Walnut and Ash trees throughout the county.
◦ Emerald Ash Borer identified April, 2012
Contacts for Compliance Agreements initiated by PDA.
Mulch Facilities Signed
Firewood Producers Signed
Sawmill Signed

14. Why a Quarantine
Slow the spread of TCD
Allows management of regulatory
articles to
move after mitigation complete
Surveys to determine how dispersal of pests
Assists in continuation of trade

15. Internal and External Quarantine

16. Compliance Requirements
Mulch
temperature requirements 160
degrees at 18 inches instead of 140
degrees required for EAB
All Firewood is considered Regulated
Article unless heat treated and certified.
No “Green” Walnut may move out of
quarantine area.

17. Tree Removal February 2012

18. Sampling Prior to Tree Removal
February 2012

19. 2012 Surveys Conducted

20. Survey 2013

21. Survey Results for 2012 & 2013

22. Sampling
 WTB
are active at 40 degrees or higher and can chew
through plastic baggies.
 Freezing samples for 24-48 hours not adequate
 WTB samples should be placed in alcohol.
 Samples to ID Geosmithia should be in a hard container
with ice packs in a sealed cooler
 Identify the tree sampled.
 PDA must have an official sample to implement
quarantine.
 PDA requires a positive identification of both WTB and
Geosmithia to implement quarantine.
 If not sure, contact Sven or Dana at PDA

23. Sampling

24. Regulatory
Quarantine
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Individual
Community
County
State
Interstate
International

25. Conclusions
Cooperation
allowed for quick response
to threat of TCD
Survey efforts have maintained trade with
most states
Good working relationship with property
owner, extension, university, state and
federal partners
Better understanding of industry and
regulatory relationships

26. Additional Sources for Information
http://pda.state.pa.us/ThousandCankersDisease
Website includes Quarantine Order, explanation of quarantine, compliance
agreement stipulations, color photos, fact sheets.
PA INVASIVE SPECIES HOTLINE: 1-866-253-7189

27. Contact
Dana Rhodes
Plant Inspection Program Specialist
danrhodes@pa.gov
717-772-5205