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Tree-of-Heaven

Ailanthus altissima
Updated Oct 27, 2024
 
1

Make a Positive Identification

Tree-of-heaven is an invasive tree that spreads quickly and is difficult to control. It thrives in harsh sites, as shown in the photo above. Tree-of-heaven grows an extensive root system that produces new stems which emerge far away from the trunk of the established tree.

Species: Tree-of-heaven
Tree-of-heaven tree against sky
Many tree-of-heaven stems growing in abandoned building foundation
Photo credits
Left:

Richard Gardner, Bugwood.org (cropped)

Right:

Joseph M. DiTomaso, University of California - Davis, Bugwood.org (cropped)

Tree-of-heaven is a fast-growing deciduous tree. It grows as a single tree (left) or as many stems (right).

Species: Tree-of-heaven
Large tree-of-heaven leaf with leaflets

Karan A. Rawlins, University of Georgia, Bugwood.org

Leaves have a large central stem with leaflets arranged opposite each other along the stem. A single leaf is 1–3 feet long.

Species: Tree-of-heaven
Textured bark of mature tree-of-heaven tree
Tree-of-heaven bark
Photo credits
Left:

Annemarie Smith, ODNR Division of Forestry

Right:

Paul Wray, Iowa State University, Bugwood.org

Mature trees grow as a single trunk up to 100 feet tall. Bark is textured and colored shades of brown and gray as trees age (left photo). The bark of younger trees is smooth and brownish-green (right photo).

Species: Tree-of-heaven
Tree-of-heaven fruits hanging on branch

Annemarie Smith, ODNR Division of Forestry, Bugwood.org

Established female trees produce hundreds of thousands of seeds each year. The seed forms inside clusters of samaras and remains on the tree through winter.

Species: Tree-of-heaven
Many tree-of-heaven stems in grassy area

Robert Vidéki, Doronicum Kft., Bugwood.org

Tree-of-heaven has an extensive root system, including shallow roots. The shallow ones produce many shoots that emerge far from the trunk of the established tree.

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LOOK-ALIKES: BLACK WALNUT AND SUMAC
Species: Tree-of-heaven
Highlighted notched base on tree-of-heaven leaflet

Chris Evans, University of Illinois, Bugwood.org (modified)

Tree-of-heaven’s leaves have a notched base on each leaflet as highlighted by the white box in the photo.

Species: Black Walnut
Highlighted rounded base on black walnut leaflet

Paul Wray, Iowa State University, Bugwood.org (modified)

Black walnut (Juglans nigra) leaves have a rounded base on each leaflet as highlighted by the white box in the photo. When crushed, black walnut leaves have a distinctive walnut family smell. Use gloves to keep the sap off of your skin.

Tolerate if possible

Black walnut is a desired tree species (native to eastern North America) that doesn’t require control in most situations.

Species: Sumac
Sumac leaves with rounded base

John Cardina, The Ohio State University, Bugwood.org (modified)

 

Sumac (Rhus spp.) leaves also have a rounded base on each leaflet. Many sumac varieties have serrated (jagged) leaf edges as shown in the photo.

Different risks or methods

Sumac species are planted in landscapes. They spread by underground roots. Leave sumac alone or pull up stems and cut root runners to contain it as needed.

Spotted Lanternfly, An Invasive Species of Concern in the Pacific Northwest
Species: Spotted Lanternfly
Cluster of spotted lantern flies on tree

Richard Gardner, Bugwood.org

Spotted lanternfly (Lycorma delicatula) is an invasive insect species. Its preferred food source is tree-of-heaven. Spotted lanternfly nymphs and adults cause feeding damage to many different plants in landscapes, farms, and natural areas.

In the mid-Atlantic states of the US, spotted lanternfly is causing damage to a wide range of plants in farms and landscapes causing significant economic harm.

Take action

Spotted Lanternfly in Oregon

The spotted lanternfly is not known to occur in the Pacific Northwest, but the habitat will likely support this invasive insect.

See Pest Alert: Spotted Lanternfly is an Invasive Insect That May Impact Oregon (OSU Extension Service).

If you suspect you’ve seen spotted lanternfly, please report it to pestreport@oda.state.or.us  (Oregon Department of Agriculture).

Free help Identifying Weeds, Insects & Pests
Get expert pest management info & advice online from OSU's Ask Extension.
Get Help
 
2

Tree-of-Heaven Benefits

  • Tree-of-heaven is a favored food of invasive Spotted Lanternfly (SLF). Pest managers may use the trees to help detect, monitor, or control SLF populations 
    Tree-of-heaven grows quickly and provides shade. In the past people valued it for those reasons. However, many other trees provide the same services without being invasive.
  • The benefits of tree-of-heaven are outweighed by the risks.
 

Tree-of-Heaven Risks

  • Tree-of-heaven is an aggressive tree that quickly takes over an area.
  • It degrades habitats and damages sidewalks and building foundations. It thrives in harsh sites.
  • Tree-of-heaven spreads easily. It is a prolific seed producer. Established trees spread with shallow roots that produce many shoots.
  • Tree-of-heaven is difficult to control.
  • Tree-of-heaven attracts and feeds spotted lantern flies, another invasive species.

Tree-of-heaven can affect human health

  • The pollen is an allergen to many people. In addition, the sap from leaves, stems, and fruits (samaras) is moderately irritating to human skin.
  • Use protective clothing and gloves when handling tree-of-heaven plant material.
Risk Card
Does it cause harm?
Adults & Children
Some
Property
High
Pets
None
Annoyance
High
Environment
High
Action Highly Recommended
 
3

TAKE ACTION

Tree-of-heaven spreads quickly and is difficult to control. Don’t ignore saplings and clusters of stems.

Do I need to take action?
Yes. If you have established stands of tree-of-heaven on your property, set realistic management goals and take a multiyear approach.

What if I do nothing?
Left alone, tree of heaven dominates areas, including neglected areas, landscapes, and natural areas.

 
4

PREVENT TREE-OF-HEAVEN

Tree-of-heaven seedlings with 1-2 sets of true leaves

Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

Control Tree-of-Heaven Regrowth and Seedlings
  • Return to areas where you cut tree-of-heaven stems or applied herbicide and remove regrowth. Expect to re-treat for two or more years.
  • Visit the treatment area in late winter and early spring. Look for tree-of-heaven seedlings like those shown in the photo. Remove seedlings.
  • The seeds survive about 1 year in the soil. They don’t develop a persistent seed bank in the soil.
Landscape area with native plants growing densely together

Weston Miller, Oregon State University

Replant the Affected Area
  • Tree-of-heaven does not thrive in dense shade. But seedlings will persist under shade and wait for a gap to open in the canopy.
  • After you implement a tree-of-heaven control program, replant the area. Replant with a variety of native shrubs, trees, and ground covers.
  • After tree-of-heaven is removed, the desirable plants that were buried underneath tree-of-heaven stems often regrow.
  • Replanting is necessary when tree-of-heaven removal significantly damages a site and few or no desirable plants remain.
  • Replanting stabilizes the soil surface and shades tree-of-heaven seedlings.
Area damaged by invasive plants growth and removal replanted with native plants

Carmen Hauser, iStock

Replant Larger Areas with Technical Support
  • Tree-of-heaven is difficult to eliminate from an infested area. Replanting a previously infested area requires planning and effort.
  • Create a multi-year revegetation plan. Plans include site preparation and planting details, plant care, and follow-up control for tree-of-heaven and other weeds.
  • Plan for at least 2-3 years of monitoring and maintenance.
  • Your local Extension specialist, soil and water conservation district, or a professional revegetation specialist can suggest strategies for your area.
 
5
SOLUTIONS FOR TREE-OF-HEAVEN

Early Detection & Rapid Response

Watch for tree-of-heaven on property you manage. Remove it before it becomes a bigger problem.

Physically Remove Plants

  • It’s possible to remove tree-of-heaven seedlings and saplings with digging tools. Once established, tree-of-heaven is difficult to remove physically.
  • Tree-of-heaven roots send up suckers (clones) that may appear to be seedlings but are attached underground to the parent tree. Physically removing suckers can be difficult. Cutting down a tree without killing it first (with herbicides) will lead to new suckering stems.

Herbicides (Weed Killers)

Herbicides effectively kill tree-of-heaven when used according to label directions.

Monitoring & Follow-Up

  • Controlling tree-of-heaven takes several years of action and monitoring. It is very difficult to control.
  • After you remove tree-of-heaven, new plants will grow in the same spot unless you take steps to prevent them.

NEED HELP?

Consider a licensed pest control company. Learn How to Hire a Pest Control Company.
Your local Extension Specialist in Oregon  and other states  can suggest other methods.

Jump to

Method Does it work? Is it safe? Recommendation
A
Physically Remove Plants
Somewhat effective
Low risk
Recommended
B
Control with Herbicides
Effective
Moderate risk
Use if Necessary
C
If Using Herbicides, Protect Yourself & Minimize Risks
 
A

Physically Remove Plants

Non-Chemical Method

Richard Gardner, Bugwood.org

Physically Remove Plants

Recommended

Dig out small tree-of-heaven trees with hand tools before they develop extensive root systems.

Does it work?
Somewhat effective
  • It’s possible to remove tree-of-heaven seedlings and saplings with digging tools.
  • Use preventive measures for best results.
How much effort?
High effort
  • Dig out saplings and small trees. Remove the entire root system.
  • Monitor for regrowth and take action as needed.
What's the risk?
Low risk

Contact with tree-of-heaven leaves, branches, seeds, and bark may cause skin rashes. Wear a long-sleeved shirt and gloves.
Possible risk of exposure or harm from chemicals
NONE

Be Realistic About Removing Tree-of-Heaven

  • Once established, tree-of-heaven is difficult to remove physically without the aid of heavy equipment.
  • If you dig out large tree-of-heaven plants, expect root pieces to break off in the soil. New stems will grow from roots left in the ground. Take action as needed.

Soil Disturbance & Erosion

  • Minimize soil disturbance as much as possible when removing tree-of-heaven.
  • Regrade the soil after digging out roots. Apply mulch (when appropriate).
  • Take steps to prevent erosion as needed.
  • Replant the area to shade out more weeds.
 
B

Control with Herbicides

Chemical Method: Use with caution

Chameleonseye, iStock

Control with Herbicides

Use if Necessary

Controlling tree-of-heaven with herbicides often requires advanced herbicide application techniques described below.

Does it work?
Effective
  • Herbicides, used individually or in a mixture, are effective chemical treatments for tree-of-heaven.
  • Use preventive measures for best results.
How much effort?
High effort
  • Treat individual trees and patches of tree-of-heaven using a combination of the herbicide application methods described below.
  • You'll need to remove standing tree-of-heaven trees after they die from an herbicide application. Get professional help as needed.
  • Several years of monitoring and effort are required to get rid of tree-of-heaven.
  • Return to the area each year and take action as needed.
What's the risk?
Moderate risk
  • Herbicides come with real risks. ALWAYS read the entire label front to back. Review instructions even for brands you know.
  • Herbicides can run off your site into waterways and may harm wildlife. See How to Keep Pesticides Out of Waterways.
Possible risk of exposure or harm from chemicals
El uso de herbicidas conlleva cierto grado de riesgo. El riesgo más bajo se presenta con el uso de métodos alternativos.

You may be exposed to an herbicide if you:

  • Get it on your skin
  • Breathe it in
  • Eat or smoke afterward without washing hands
  • Touch or eat plants that are wet with spray (you, pets, or children)
  • Bring it inside on your shoes or clothes

Follow directions closely to reduce risk.

Some herbicides are available for home use. A few are listed below.  These products used individually or in a mixture are effective chemical treatments for tree-of-heaven. Look for these chemical names in the “Active Ingredients” section of product labels.

  • Glyphosate
  • Imazapyr
  • Triclopyr

Suggested active ingredients are from the Pesticide Information Center Online (PICOL) Database. They are permitted for HOME use in Oregon. Read the label for application directions and effectiveness information.

ONLY professional pesticide applicators can use Restricted-Use Pesticides (RUP) that may be more effective. For larger stands of tree-of-heaven contact a licensed pesticide applicator with experience controlling tree-of-heaven.

Tree-of-heaven tree with many stems and leaves

Richard Gardner, Bugwood.org

A small stand of tree-of-heaven is still manageable, but action is needed soon before the trees get bigger and more difficult to remove.

Herbicide label highlighting active ingredients glyphosate and imazapyr

Weston Miller, Oregon State University

The white box on this example product label highlights active ingredients glyphosate and imazapyr. These ingredients will damage most plants and grasses. Don’t let the spray contact plants you want to keep.

Herbicide Application TIPS

  • Premixed products are available in hardware stores and garden centers.
  • The key to getting rid of tree-of-heaven is to return to areas where you manage it. Expect to re-treat for two or more years.
  • The best time to treat tree-of-heaven is mid summer to early fall. Herbicide applications made outside of this time frame more often injure the above-ground growth rather than kill the root system.
  • Use a combination of foliar (leaf), basal, bark, and frill herbicide application methods described below.
  • Cut-stump herbicide applications encourage shallow roots to produce shoots and shouldn’t be used for tree-of-heaven unless you intend to treat the regrowth and the new shoots.
  • See below for more information about these herbicide application methods.
Herbicide products for tree-of-heaven will kill most plants and grasses. Don’t let the spray contact plants you want to keep.

 

Herbicide Application Methods

Foliar (leaves), basal bark, and cut-stump application methods all effectively kill tree-of-heaven. Choose the right method for your situation.

Worker spraying herbicide on tall foliage

Max Williamson, USDA Forest Service, Bugwood.org

Foliar (Leaves) Application

  • Foliar (Leaves) Application
  • Only spray herbicide on the foliage of btree-of-heaven when nearby plants can be avoided. The spray could damage plants you want to keep.
  • The foliar method works for small seedlings and clones. For larger stems, consider the frill application method.
  • A backpack sprayer is effective for treating small areas.
  • For large infestations, start with a foliar application to kill the seedlings, saplings, and shoots. Follow up with basal-bark or frill applications on the remaining stems.
Diagram of basal-bark herbicide application technique

James H. Miller, USDA Forest Service, Bugwood.org

Basal-Bark Application

  • This is best for stems less than 6 inches in diameter.
  • Concentrated herbicide (oil soluble) is mixed with another ingredient (adjuvant), typically a seed oil.
  • The mixture is sprayed on stems from the ground to a height of 12–18 inches.
  • The plant absorbs the herbicide sprayed in the trunk. The herbicide moves to the roots.
Worker using frill herbicide application method

James H. Miller, USDA Forest Service, Bugwood.org

Frill Application

  • This approach is useful for stems 1 inch in diameter and larger.
  • Use an axe to make cuts spaced around the circumference of the stem.
  • Apply concentrated herbicide solution to the cuts. Make an axe cut for every 1 inch of diameter of the stem, with a minimum of 2 cuts.
  • Leave uncut areas between the axe cuts. It allows the plant to move the herbicide to the roots.
 

If Using Herbicides, Protect Yourself & Minimize Risks

Chemical Method: Use with Caution
Blue heron in marsh

BrianLasenby, iStock

Why is it important to read herbicide labels?

  • They have detailed information on how to use the product correctly and legally.
  • They contain information on potential hazards of the product.
  • They provide instructions you should follow for poisonings and spills.
  • Following label instructions helps you to minimize the risks and maximize the benefits.

Key Herbicide Safety Tips

  • Read the entire label front to back.
  • Follow the instructions.
  • Review the instructions even for brands you know.
  • Only apply the product where the label says it may be applied.
  • Be precise in your application. More is not better.

The Label is the Law

ALWAYS read the label before using herbicide products. The label is a legal document that provides information on how to safely use the herbicide. This helps avoid harm to human health and the environment. Using an herbicide in off-label ways is illegal. It can result in legal enforcement actions.

READ THE LABEL & Follow Instructions
It has instructions to protect you and the environment.

  • Labels are different for every product and they often change over time.
  • Use a magnifying glass for small print.
  • Pay attention to CAUTION, WARNING, and DANGER statements.
  • Pay attention to the PRECAUTIONARY STATEMENTS.
  • The law states you must read and follow herbicide instructions.

Protect Yourself
Eye, skin & lung irritants

  • Wear the right protective gear. This often includes chemical-resistant gloves, safety glasses, a long-sleeve shirt, pants, socks, and shoes.
  • Mix outdoors or in a well-ventilated area.
  • Wash hands after mixing or applying, and before eating or smoking.
  • Take a shower immediately after handling herbicides.
  • Wash clothes worn while mixing or applying separately from other laundry.

Protect Children & Pets
Children and pets are at risk if they eat or touch the plants before it dries.

  • Keep them away during and after applying herbicides (read label for how long).
  • Remove toys and pet dishes from yard before applying.
  • Don’t track herbicide products into your home on shoes or clothes.

Protect Plants You Want to Keep

  • Glyphosate and similar herbicide ingredients damage both grass and broadleaf plants.
  • Minimize spraying of foliage, stems, exposed roots, or the trunks of desirable shrubs or trees to avoid harm.
  • Follow the label to avoid damaging the roots of trees and shrubs.

Don’t Spray into Water

  • It’s illegal to apply herbicides in a stream or slow moving/wetland pool.
  • You need a product registered for aquatic areas. This includes waterways, ditches, drains, and other places where water collects.

Avoid Wet, Windy, or Hot Weather
Use during favorable weather for best results.

  • Don’t spray when it’s raining or when rain is expected in the next 24 hours.
  • Wind causes spray to drift that can get on you and desired plants.
  • Herbicides may be less effective in hot weather if the target plants are moisture-stressed.
  • Some herbicides can turn into a vapor in hot weather and damage nearby plants.

Storage & Disposal

  • Store in a secure area away from children.
  • Don’t put unused herbicide products in the trash.
  • Never pour down any drain or waterway.
  • Take unused herbicides to a hazardous waste facility.

Call  1-800-CLEANUP (1-800-253-2687) to find out where to dispose of herbicides.

For the Portland metro region in Oregon, contact Metro’s Recycling Information. Call  503-234-3000, email   or visit Metro’s website  

More about:

About Using Pesticides on School Grounds in Oregon

If using pesticides on school grounds, there are special rules in Oregon. See School Integrated Pest Management  (Oregon Department of Agriculture).

NEED HELP?

The National Pesticide Information Center (NPIC)  can answer questions about pest control chemicals.
 1-800-858-7378 or npic@ace.orst.edu  

Consider using a licensed pest or weed control company. Learn How to Hire a Pest Control Company.

Your local Extension Specialist in Oregon  and other states  can suggest other methods.

Invasive Species Alert

  • Invasives are non-native species that spread aggressively and alter the environment.
  • Controlling unwanted tree-of-heaven is costly.
  • Please do your part to control it on property you manage. It can spread beyond your property and have an adverse impact on your neighbors.

If you think you’ve found tree-of-heaven anywhere in Oregon, please report it to the Oregon Invasive Species Hotline at:  1-866-INVADER (1-888-468-2337) or use their online reporting form  

open Map static invasive map
Invasive species data @ 2022, iMapInvasives (NatureServe)

If you find tree-of-heaven anywhere in Oregon, please report it   State officials are mapping the distribution of this invasive species.

View Larger Map >
SEE OTHER COMMON PACIFIC NORTHWEST WEEDS

Content provided by editor Weston Miller and writers Jessica Green and J. Jeremiah Mann. Pesticide safety information edited by Kaci Buhl.

  Peer review facilitated by OSU Department of Horticulture.

Photo of Weston Miller

Weston Miller

Project Founder and Content Writer

Weston Miller served as Community and Urban Horticulture faculty for Oregon State University Extension Service for Clackamas, Multnomah, and Washington Counties. Weston is an author for content for this website. He developed funding partnerships with Portland area agencies to initiate and build out the Solve Pest Problems website focused on this goals:

Photo of Jessica Green

Jessica Green

Jessica Green has held various positions at Oregon State University for over 15 years. She was one of the original content contributors for Solve Pest Problems and now assists with maintaining the resource for the Oregon IPM Center. Jessica is a contributing author/editor for the PNW Weed and Insect Management handbooks, has designed and conducted research trials, and now serves as an educator for OSU's Pesticide Safety Education Program (PSEP).

J. Jeremiah Mann

J. Jeremiah Mann

J. Jeremiah Mann completed a Physical Science undergraduate degree at Humboldt State University, and M.S, Ph.D focusing on plant science topics at UC Davis. He went on to work for the Natural Resources Conservation Service and in a leadership position serving a private agricultural technology company. He currently lives in Sacramento California where he consults on pest and property management topics.

Photo of Kaci Buhl

Kaci Buhl

At the state level, I lead the Pesticide Safety Education Program (PSEP). The program hosts live recertification events around the state, serving over 1,000 licensed pesticide applicators each year. We also produce web-based training modules and license-preparation study manuals. Special training for unlicensed pesticide applicators is also available through a grant from the USDA Specialty Crop Block Grant Program. The PSEP at OSU works closely with the Oregon Department of Agriculture's Pesticides Division.

TREE-OF-HEAVEN REFERENCES

Tree-of-Heaven  
Penn State University

Tree-of-Heaven  
Washington State Noxious Weed Control Board

A Tale of Two Invaders: Tree of Heaven and Spotted Lanternfly
Michigan State University Extension