Tree of Heaven (Ailanthus altissima)

Presentation by Chris Asaro, VA Dept of Forestry

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

County distribution of TOH

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%

Timber Volume by Species in VA (ft3)

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

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

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

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

Ailanthus Control/Harvest Study

Presenter

Presentation Notes

Identification: Small- to medium-sized, smooth gray bark, compound alternately pinnate leaves, dioecious, flowers, leaves, and twigs smell like burnt peanut butter. Ecological Threats: 350,000 wind-dispersed seeds per year per tree; seedlings have a taproot within 3 months of germination. Quickly overruns native species in competing for light and space. Toxin in bark and leaves inhibit growth of other plants.

Tree of Heaven Thicket

Tree of Heaven months after basal bark treatment with Garlon 4

Utilization of Ailanthus

Natural Hardwood Charcoal

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!

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.

Wilting

Initial Severe

Ailanthus Wilt Photo Guide Courtesy of Dr. Donald Davis, Department of Plant

Pathology, Penn State University

Vascular Discoloration

Healthy Ailanthus Wilting Ailanthus

Declining Trees

Mortality

Seedling Inoculations

Controls Inoculated

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.

E. brandti Life Cycle

5 days

110 days

16 days

33 days

164 days at 25oC Most

damaging stage to TOH

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

?

• 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

(ArcGIS 10 and ArcMap 10 software from ESRI 2011)

11,000 miles surveyed

(ArcGIS 10 and ArcMap 10 software from ESRI 2011)

85 symptomatic sites sampled

(ArcGIS 10 and ArcMap 10 software from ESRI 2011)

Six V. albo-atrum sites found

(ArcGIS 10 and ArcMap 10 software from ESRI 2011)

Initial counts of all sites in VA

• As of September 2011:

4,825 TOH are dead or dying from Verticillium albo-atrum in Virginia.

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

Questions?