Chemical and Biological Control of Ailanthus altissima, the Last

of 3 Presentations

Richard Gardnerrtgardner3@yahoo.com

(410) 726-3045

ABSTRACT: This is the third and final presentation on Ailanthus altissima (Tree-of-Heaven). It will show that Ailanthus altissima is easy to kill by chemical methods 24/7/365. At the same time, over several states and

years, a naturally occurring biocontrol system has been observed that is effectively killing Ailanthus altissima. This serves as a model for finding biocontrol systems

for other invasive non-native organisms and ending the scientifically unsound practice of introducing yet more

non-native organisms to control current and future problems.

Tree Physiology

Early in the life of Ailanthus the main root makes a right angle turn that is parallel with the ground as seen in this photo and the following.

Fluid flow is along a line @ 2” wide from the injection to the apical

meristems in the roots and branches.

This was found out by drilling a hole into the trunk and injecting 50.2% glyphosate then tracking

the death of the leaves and vascular cambium.

flu

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f

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Injection point

Injection point

The left fork of this trees was poisoned about 2 weeks before this photograph.

This and similar experiments were performed on several trees.

Male trees – notice the single clean peduncles

peduncle

peduncle

Female tree – notice the elaborate branching peduncles and seeds.

peduncles

peduncles with seeds

Biocontrol

Atteva aurea – the Ailanthus

web worm, super defoliator, taxi and disease vector.

A. aurea, November 19, 2012 on Solidago sp. along Blue Marsh, Berks County, PA.

egg

egg

larva

empty pupa shell

egg

larva

larva

larvae entering into pupa stage

pupae

This is a young tree full of communal A. aurea webs, a

common sight.

In this location 100% of the trees of all age groups had A.

aurea webs.

Communal webs

Another young tree with communal webs and disease

as shown by the dead branches and chlorosis.

chlorosis

Some A. aurea adults are apparently overwintering in central Pennsylvania as evidenced by the adults found feeding on Solidago species into late fall and the finding of larvae early after A. altissima goes

into leaf.

This could be caused by basic evolution as the A. aurea adapts to colder temperatures due to the availability of a new food source or due to global

warming.

It is most probably a combination of both.

The one question I have not been able to answer is the nectar source for A. aurea before

mid-summer.

I am assuming that the food source is a native Asteraceae as the later summer food sources I

have seen are Asteraceae family members.

Aculops ailanthii – killer of the young, bringer of disease and

death.

Diseased tree with Aculops ailanthii infestation.

Aculops ailanthii and chlorotic leaves on a mature tree.

A. aurea herbivory

A. Ailanthii mottling of leaves

A. aurea web

Fusarium and Verticillium –the third strike and death blow,disease strikes hard and fatally.

Fungi that infect A. altissima

Fusarium lateritium – lesionsFusarium oxysporum - wilt

Fusarium solani – lesions and wiltVerticillium albo-atrum - wilt

Verticillium dahliae - wilt

Fusarium lateritium macroconidia

Plate with Fusarium from diseased tree

Fusarium macroconidia from diseased tree.

Fusarium macroconidia from diseased tree.

Fusarium micro and macroconidia from diseased tree.

Fusarium micro and macroconidia from diseased tree.

With Atteva aurea, Aculops ailanthii and pathogens working

together death is certain.

Urbana, MD Community Park, September 2007.

The same stand in July 2011.

Pine Swamp Road, near Hawk Mountain, Fall 2011

Pine Swamp Road, near Hawk Mountain, August 2012.

Blue Marsh, August 2012

Blue Marsh, December 2012.

Compound leaf with A. aurea larvae and A. ailanthii.

This is the first biocontrol system I recognized, SGL 106 near Hawk Mountain, PA.

Birds – best for long distances

Moths – best for medium and short distances

Wind – best at short distances with high mite and tree densities

Transport of Aculops ailanthii across landscapes

Transport of Aculops ailanthii across landscapes

From recent walking it appears that there is a correlation between the density and nearness of the nectar sources adult Atteva aurea feed on

and the amount of disease in a stand of Ailanthus.

The key to finding a native biocontrol (system) for plant is to find an organism which is a generalist

herbivore for a family or genus and a specialist to that family or genus.

This means that the biocontrol has a the genetic ability to switch from one

plant to another and yet will not cause the extinction of coevolved food

sources.

A. aurea larvae eat other Simbouracae family members, but only eats

members of this family.

A. aurea larvae will preferentially eat a non-coevolved food source because it does not have the defenses to it that a

coevolved food source has.

Hence, an easy meal that is a higher quality food source (higher energy return for energy expended) than a

native coevolved one since it spends less energy dealing with chemical and

physical defenses.

At the same time it is embedded in a system of a mite (A. ailanthii) and

several diseases.

Which together interact to cause control of A. altissima.

Unique features of this system:1. A. altissima is the only food for A. aurea larvae in most of the A.

altissima range2. A. aurea adults are generalist nectar feeders

3. A. ailanthii is an apparent specialist to A. altissima4. A. aurea larvae have no other local food sources so the adults have spread themselves beyond their normal range by following

nectar sources and egg laying sites.5. A. aurea and A. ailanthii are the vectors for several A. altissima

diseases6. A. ailanthii apparently hitchhikes between A. altissima trees on

birds and A. aurea.7. A. aurea appears to evolving to colder temperatures as witnessed

by their presence feeding on goldenrod in central Pennsylvania in mid-November after frost and freeze.

How to develop an Ailanthusbiocontrol system:

1.) Do not apply pesticides to the surrounding area – herbicides,

insecticides, fungicides, … .

2. Plant a wide variety of native high nectar flowers nearby so there are

high quality food sources from mid-spring to first heavy freeze for the

adults to feed on.

So far I have found adult Atteva aurea on daisy-like flowers and at least 2

species of goldenrod from August to mid-November. I am still not sure

what they feed on from early spring when the Ailanthus leaves are just beginning to bloom to mid-August.

Chemical Control:Drill and Fill -

effective 24/7/365

This method was developed as a safe and efficient method for volunteers to

use in contained areas such as a township park.

Bartram Trail on May 31, 2012 of tree injected January 10, 2012.

Drill a 3/8” hole through the vascular cambium every 2” of girth at comfortable working height.

3/8” drill holes @ every 2” apart

Then spray 50.2% glyphosate (purple cap RoundUp®) into the

holes with a spray bottle.

If done in the summer, within a

week the leaves will begin

wilting and yellowing.

Within 2 weeks the leaves will

begin falling.

If the method is done in the winter, there may be a few vestigial leaves that try to form as it comes out of

dormancy.

However, the tree will still be dead by the end of the summer.

One day after injection in July 2011.

8 days after treatment in July 2011.

11 months after treatment, June 2012.

Day 0 at another location. I did this “as a volunteer” to test the robustness of the method.

Two weeks after injection.

End of summer at same site.

Day 0, five trunks with DBH from 8” to 44”.

17 days after injection.

Same stand in October, 4 months after injection.

Tree injected on January 10, 2012 then felled by Hurricane Sandy, October 29, 2012. Notice the burrows of ambrosia beetle Euwallacea

validus, (identified by Dr. Matthew T. Kasson) originating in the drill holes.

Small tree injected in June 20 then felled by Hurricane Sandy, October 29, 2012.

The three sure signs of tree death are:1.) no green layer under the bark

when scraped, 2.) white fungi growing around the

outside of the tree and 3.) loose/peeling bark.

It is essential that all dead trees around trails, roads and buildings be cut down within six months of dying.

Several trees poisoned in January and June 2012 fell in late October with

Hurricane Sandy.

Due to its exceptional growth rate Ailanthus does not develop the internal structures denser trees

develop which give them strength.

Once it dies, the tree falls and decomposes swiftly.

The reason this method works 24/7/365 is that glyphosate is

degraded primarily by microbes and not metabolized or detoxified by the

tree.

During tree dormancy the microbe population decreases substantially due

to severely slowed fluid flow within the tree and low environmental

temperatures.

As the tree moves out of dormancy and the sap begins to flow the

glyphosate poisons the tree most likely by killing the vascular cambium both ways along the vertical line between the injection site and the ends of the roots and stems while also poisoning the meristem tissue in the roots and

stems.

Method advantages:

1.) It does not use sharp blades. This reduces the potential for injury.

2.) All the materials can be found relatively inexpensively in most

hardware stores.

3.) Feedback is fast and can be watched as it develops. The results begin to show in less than one week with nearly complete defoliation of

trees in less than three weeks.

4.) This method can be done in the winter when the amount of brush is diminished and there are no biting

insects.

5.) Lastly, this method appears to be robust and may work on other plants such as Lonicera morrowii, Lonicera maackii, Broussonetia papyrifera,

Elaeagnus umbellate or other invasive woody plants.

In summary, this is an easy and safe volunteer friendly method which is effective in eliminating Ailanthus altissima in discrete areas such as

parks. At the same time it is usable by professionals to cheaply remove

Ailanthus from small landscapes with a minimum of equipment and time.

Glyphosate environmental

non-target organism effects

Over 24 days there was an experiment to measure the affect of glyphosate in dropped leaves on plants, in this case a

lawn grass mixture.

Glyphosate in dropped leaves toxicity experiment on grass, day 0.

Glyphosate in dropped leaves toxicity experiment on grass, day 24.

• 16 trays were filled with potting soil and various grass seed mixtures over the summer. They were then placed under a row of mature Spruce trees.

• August 15, 2012 several branches were pruned from tree #2 before injection and the leaves frozen in 1 gallon Ziplock® bags.

• August 15, 2012 50.2% glyphosate was injected into 2 trees, #1 and #2 through 5/16” x 1-2” holes

• Leaves were collected after they fell, about 1 week later, and stored in a freezer.

• On August 31 the leaves were then spread across 16 trays of mixed lawn grass in potting soil as follows:o 2 trays left untouched, blank controlo 2 trays with water only, water controlo 6 trays with 100 grams leaves picked from trees before

injection with glyphosateo 6 trays with 100 grams glyphosate leaves

• On September 24, 2012 the experiment was concluded with no apparent differences between any of the trays.

Experiment Protocol

Other application:Paper mulberry,

Broussonetia papyrifera, killed by

Drill and Fill to demonstrate the

method robustness.

Future research1.) determining the food sources of

Atteva aurea in the late spring and the first half of summer.

2.) growing a biocontrol garden specific to Atteva aurea and Ailanthus

altissima control.3.) determining to the family the fungi that are infecting Ailanthus altissima

and their carriers.

The best way of destroying stands of Ailanthus altissima:

Plant native Asteraceae near the trees and leave alone.

The second best way to deal with Ailanthus altissima:

1.) Drill and Fill large trees.2.) Plant native Asteraceae nearby and

leave alone.

Ailanthus altissima biocontrol garden.

Ailanthus altissima biocontrol garden

2. Aster laevis 1. Asclepias tuberosa4. Erigeron speciosus 3. Aster novae-angliae6. Eupatorium perfoliatum 5. Eupatorium maculatum8. Monarda fistulosa 7. Heliopsis helianthoides10. Rudbeckia laciniata 9. Rudbeckia hirta12. Solidago canadensis 11. Rudbeckia triloba14. Solidago rigida 13. Solidago nemoralis16. Verbesina alternifolia 15. Solidago speciosa18. sunflowers 17. Asclepias syriaca19. Coreopsis 20. Shasta daisy21. sweet peppers 22. sweet peppers23. sweet peppers 24. Eu. mac./Cor.

trip./Ech. pur.

25. Collected plants

pasture uphill driveway

• originated in the neotropics and migrated north when a new food source was available – Ailanthus altissima.

• breed from early in the season until hard freeze – no diapause, this reinforces that they have not had enough time to change from a warm climate to a temperate species.

• females mate in the morning and then lay eggs in the evening.• webs are multigenerational with adult females laying eggs on the

webs made by other larvae.• from egg to adult is @ 21 days.• adults apparently overwinter at least as far north as central

Pennsylvania. • adults have at least a two color morphs, standard

orange/black/white and the same with a reddish cast.• adults are generalist nectar feeders at least in the Asteraceae

family.

Interesting facts about Atteva aurea

• larvae eat the young bark as well as leaves of Ailanthusaltissima, but no other plants.

• larvae have several color morphs from black to light brown and greenish.

• larvae form “tents” before they enter into the pupal stage by biting mostly through the rachis (mid-vein) of a compound leaf and letting it drop, then making a web around the resultant structure.

• aposematism is the primary defense in the same way as monarch butterflies – bright, colorful and easy to catch suggesting that there is no need for other defenses. Ailanthus altissima ingested as a larva probably make the larvae and adults unpalatable.

• easy to catch and easy to raise.

Facebook:

Ailanthusresearch

Biocontrol/

Richard Gardnerrtgardner3@yahoo.com

(410) 726-3045