Presentation on the invasive Tree of Heaven given by Chris Asaro of the Virginia Department of Forestry at a May 2012 invasive plant workshop.

1. Tree
of Heaven
(Ailanthus
altissima)
Presentation by Chris Asaro,
VA Dept of Forestry

3. Worldwide distribution of A. altissima (Ding et al. 2006, Kartesz 2011, DiscoverLife
2011).

4. County distribution of TOH

6. Timber Volume by Species in VA (ft3)
Rank Name Total %
1 yellow-poplar 4,628,662,842 14.7%
2 loblolly pine 3,717,977,305 11.8%
3 chestnut oak 2,985,045,571 9.5%
4 white oak 2,819,621,174 8.9%
5 red maple 2,222,352,795 7.0%
6 northern red oak 1,690,241,731 5.4%
7 Virginia pine 1,533,633,995 4.9%
10 black oak 965,711,553 3.1%
11 eastern white pine 713,167,672 2.3%
29 eastern redcedar 159,196,748 0.5%
46 ailanthus 48,241,041 0.2%
75 other 4,372,982 0.0%
92 paulownia 1,245,776 0.0%

7. Tree of Heaven – History and
Use
• Original Range - Eastern China
• Origin of Introduction – Europe
• Year of Introduction – 1784
• Purpose of Introduction – Urban tree
• Desirable qualities – Pollution and
drought tolerance
• Undesirable qualities – fast growing,
prolific seeder, sprouts aggressively after
disturbance, smelly, allelopathic

8. Tree of Heaven –
Biological Highlights
• 2 to 3 yr old plants can produce viable
seed
• Up to 300,000 seeds / yr for mature tree
• Seeds disperse up to 330 ft from parent
• Sprouts can grow 10 to 14 ft tall in first
year and maintain this growth rate for up
to 4 yrs

9. Tree of Heaven -
Management Options
• Cutting and pulling should not be used
without herbicides due to vigorous
resprouting
• Burning not believed to be effective
• Target seed-producing trees first

10. Tree of Heaven –
Management Options
• Effective Herbicides
– Large trees – Garlon 3A, 4 Pathway, Arsenal
AC, Ortho Brush-B-Gon, Enforcer Brush Killer,
Vine-X
– Seedlings, Saplings – Garlon 3A, Garlon 4,
Stalker, Arsenal AP, Arsenal Powerline, Krenite
S, Escort XP
– Timing: Mid-summer best, but many products
effective year-round
• Biological Control – New possibilities on
the horizon

11. Ailanthus Control/Harvest Study

14. Tree of Heaven Thicket

15. Tree of Heaven months after
basal bark treatment with
Garlon 4

16. Utilization of Ailanthus

17. Natural Hardwood Charcoal

18. Why Utilize Invasive Species?
•Finding uses can help control their spread.
•Can help offset control costs by developing
markets for its use.
•Increases awareness of invasive species
and the impacts they can have on native
forests.
•Promoting utilization of invasive species is
part of a program to control and reduce
their impact, not encourage their planting!

19. Biological Control Efforts for TOH
at Penn State and Virginia Tech
• Verticillium albo-atrum Reinke &
Berthold (Phyllachorales)
– Soil-borne, vascular wilt fungus
– Long range dissemination is limited:
– Wind-blown leaflets, seeds and insects
– Rarely has been reported in forest
settings
– Very limited host range
Pegg GF, Brady BL. 2002. Verticillium Wilts. Wallingford, UK: CAB International.

20. Ailanthus Wilt Photo Guide
Courtesy of Dr. Donald Davis, Department of Plant
Pathology, Penn State University
Wilting
Initial
Severe

21. Vascular Discoloration
Healthy Ailanthus Wilting Ailanthus

22. Declining Trees

23. Mortality

25. Seedling Inoculations
Controls Inoculated

26. Biocontrol of TOH at VA Tech Dept.
of Entomology – Dr. Scott Salom and
Amy Snyder
• Imported
Eucryptorrhynchus brandti
(Coleoptera:
Curculionidae) Harold
from China to the VA Tech
quarantine lab in 2004
• Biology, rearing
optimization, risk
assessment, and impact
have been studied by
Herrick et al.

28. 5
days
33
days
E. brandti
Life Cycle 110
164 days at days
25oC
Most
damaging
stage to TOH
16 days

29. Could these two agents work
together in the field?
• Amy Snyder’s M.S. – Assessing E. brandti
as a potential carrier for V. albo-atrum
?

30. • E. brandti can carry the pathogen:
• internally via feces
• externally by overwintering
• were able to begin new infections on TOH seedlings by
transmission from tarsal contact
• reproduce healthy generations on infected TOH billets
E. brandti has potential for aiding in the spread
of V. albo-atrum from tree to tree because they
can carry propagules both externally and
internally

31. 11,000 miles surveyed
(ArcGIS 10 and ArcMap 10 software from ESRI 2011)

32. 85 symptomatic sites sampled
(ArcGIS 10 and ArcMap 10 software from ESRI 2011)

33. Six V. albo-atrum sites found
(ArcGIS 10 and ArcMap 10 software from ESRI 2011)

34. (ArcGIS 10 and ArcMap 10 software from ESRI 2011)

36. Initial counts of all sites in VA
• As of September 2011:
4,825 TOH are dead or dying from
Verticillium albo-atrum in Virginia.

37. Next steps… (pending EPA
approval of E. brandit release)
• Increase rearing of E. brandti
• Release E. brandti at V. albo-atrum sites and
non-infected sites
• Assess E. brandti dispersal and
establishment potential
• Restoration of sites to prevent TOH re-
intrusion

38. Questions?