Common Name: Tree-of-Heaven
Scientific name: Ailanthus altissima
Identification: Tree-of-heaven is a large deciduous tree, generally 40 – 60’ tall at maturity. Its leaves alternate along the stems, and are pinnately compound, composed of 11 to 41 leaflets per leaf. Leaflets are 3 – 5” long and often have 2 to 4 blunt teeth at the base but are otherwise smooth along the edges. Leaf stems are 1 – 3’ long. Summer foliage color is dark green. Tree-of-heaven is dioecious, which means that each individual bears only male or female flowers. The flowers, which emerge in late spring, are very small and yellow-green in color and are borne in long clusters 8 – 16” in length. Male flowers have an unpleasant odor, while female flowers have no odor. Fruits begin to form on female trees in summer. They are flat, papery chambers (samaras) with one seed in the middle. Fruits are sometimes tinged with orange or red in the summer, ripening to brown in the fall and persisting through winter. Bark is grey and marked with long, thin streaks at maturity.
Look-alikes: Tree-of-heaven in the sapling or early root sucker size class is most readily confused with native sumac species (Rhus spp.) due to the similar compound leaves and leaflet shape. However, the leaflets of sumacs are toothed along the entire margins, while the leaflets of tree-of-heaven are smooth save for one or two pairs of glandular teeth at the base. Tree-of-heaven is somewhat similar in appearance to a number of trees with compound leaves, including invasive Amur cork tree (Phellodendron amurense), and the native black walnut (Juglans nigra), yellowwood (Cladrastis lutea), and Kentucky coffee tree (Gymnocladus dioicus). Tree-of-heaven can be differentiated from all look-alikes by an unpleasant odor that occurs when the leaf stems are crushed (black walnut also has a strong smell, but it is rarely described as unpleasant). The flat, papery samaras of tree-of-heaven are also unique.
Tree-of-heaven is common throughout the eastern and central Great Lakes region (Pennsylvania, Ohio, Indiana, Illinois, and Michigan’s Lower Peninsula). It is not reported in northern Wisconsin or in Minnesota. USDA reports tree-of-heaven as being hardy to a minimum temperature of -18oF (Zone 5a), so it is unlikely to establish in the northern regions of the Basin, though its range may adjust north in the future due to climate change. This species is distributed widely nationally and has been reported in 41 of the lower 48 states. Dense infestations are frequently found near places where the species was historically used in landscaping.
Additional invasive species distribution data for specific Great Lakes jurisdictions is available from:
- Midwest Invasive Species Information Network (Michigan)
- iMapInvasives (New York and Pennsylvania)
- EDDMapS Ontario
Seed is distributed by wind and gravity, but clonal spreading from the extensive suckering root system is also common, particularly when the parent tree is damaged or stressed.
Tree-of-heaven is infamous for its weedy growth in developed and waste areas. It has been described as one of the most adaptable temperate tree species on Earth (Dirr 2019). It can also rapidly colonize disturbed forest habitats, grasslands, and riparian areas.
Tree-of-heaven often forms single-species colonies that block light from desirable native species. One factor contributing tree-of-heaven’s ability to dominate in disturbed habitats is its extremely high rate of seed production. Wickert et al. (2017) found that one individual female can produce 10 million seeds over 40 years of reproduction. It reproduces readily from the roots with suckers emerging up to 50’ away from the parent. The large root system emits chemicals that prevent other species from growing (Fryer 2010). Because it suppresses the regeneration of tree seedlings, tree-of heaven can also be problematic in timber plots.
Tree-of-heaven is a preferred food source and egg-laying site for spotted lanternfly (Lycorma delicatula), an invasive insect from Asia that was first discovered in North American near Philadelphia in 2014. Spotted lanternfly also feeds on the sap of grape vines, stone fruit trees, and certain timber trees, posing a serious threat to those industries. Lanternflies seem to return to tree-of-heaven at certain points in their lifecycle. Scientists are still researching the exact nature of the relationship between spotted lanternfly and tree-of-heaven (Finley 2018). Spotted lanternfly adults or egg sacks have been found in some of the Great Lakes counties of New York State, but these areas are not considered infested (New York State Integrated Pest Management Program 2019). However, as of the spring of 2020, spotted lanternfly has been found in western Pennsylvania and there is high risk of spread to the Great Lakes states.
Tree-of-heaven was historically planted as an urban landscape tree, particularly in ultra-urban areas, due to its ability to grow in unfavorable conditions (Dirr and Warren 2019). It is broadly tolerant of poor air quality, low nutrient soils, compacted soils, and drought. Today, it is rarely purposefully planted in North America mostly due to its invasiveness.
None. Males do not produce seed, but are not sold due to their unpleasant smell.
Please see our Landscape Alternatives pages for more information about how the WIGL Collaborative selected alternatives.
|Alternatives for Tree-of-Heaven
Common name (Latin name)
tree (>40ft tall
|Thornless honey locust (Gleditsia triacanthos f. inermis)
‘Skycole’ SKY LINE a
|Kentucky coffeetree (Gymnocladus dioicus)
|Tulip poplar / tulip tree (Liriodendron tulipifera)||✔|
|Yellow buckeye (Aesculus flava)||✔||~||✔|
|Pecan (Carya illinoinensis)||✔||✔|
|Yellowwood (Cladastris kentuckea)||~||~||✔|
~ = trait is somewhat present but not as pronounced as in check-marked examples
a Male cultivars of these species, including the ones listed, are often preferred because they don’t produce messy seed pods.
Green = native to part of the Great Lakes Basin
Yellow = native to the U.S. but not to the Great Lakes Basin
The WIGL Collaborative’s decision trees are designed to help site users, who are perhaps newly discovering that plants that are part of their home landscaping are invasive, prioritize which species should be removed first based on risk to the surrounding environment, economy, and occasionally, to human health. In a perfect world, everybody would remove all invasive plants from their landscaping right away, but in reality, removing mature woody plants involve a hefty investment of time and/or money. These diagrams can help people with multiple woody invasives in their landscaping prioritize to get the most benefit for their efforts.
To learn more about the methodology and information used to develop the decision trees and for helpful hints on how to answer the questions, please see the full report here (PDF).
The following is a brief overview of management techniques shown to be effective on tree-of-heaven. For more detailed information on how to use these techniques, visit our Management and Control page. For local assistance managing woody invasive species, please get in touch with a cooperative invasive species management group or a university extension program.
Control of tree-of-heaven is particularly challenging due to its tendency to send up root suckers if the main stem is damaged. Ineffective control can actually make an infestation worse.
Physical control: Small seedlings can be removed by hand, but this requires confirming that the small trees are actually seedlings and not root suckers from a nearby mature tree. Physical removal of larger individuals, cutting, and mowing are not effective as stand-alone practices. Tree-of-heaven suckers aggressively from the root system, particularly in response to stem damage, so top-killing methods may make infestations worse.
Chemical control and combined approaches: Herbicide applications are typically the most effective methods for tree-of-heaven because, if done correctly, they destroy the root system. Foliar, basal bark, and hack-and-squirt/stem injection application methods can all be effective, but timing is important. Extension specialists at Penn State University have found that chemical controls are most effective when applied during the peak of the growing season – roughly between July 1 and September 30 in areas of the Great Lakes Basin impacted by tree-of-heaven (Gover et al. 2008). Results of cut-stump application have been mixed, with some managers reporting excessive suckering following the treatment. In a trial conducted in Romania, researchers reported complete control of tree of heaven with diameter ranging from 1.5″ to 8″ by drilling holes and injecting concentrated glyphosate herbicide (Salceanu et al. 2021). In all cases, herbicide should be selected based on site conditions, and label directions read and followed carefully.
Several species have been studied as potential mechanisms of biological control for tree-of-heaven. These include various fungal diseases and insects. Study of some of these species is ongoing, but at the time of writing, the USDA has not approved any biocontrol agents for tree-of-heaven.
With any treatment it will be necessary to monitor for and treat regrowth and new seedlings emerging from the seed bank in subsequent years. This is especially true of tree-of-heaven due to its high potential for re-growth.
Resources on management of tree-of-heaven:
- Penn State University, Department of Horticulture 1
- Penn State University, Department of Horticulture 2
- Midwest Invasive Plant Network Control Database
- Salceanu, C., Olaru, LA., & Dobre, M. 2021. Research on the chemical control of the invasive species Ailanthus altissima from pastures. Annals of the University of Craiova – Agricuture, Montanology, Cadastre Series. 50(1): 198-203.
- Virginia Department of Forestry
- Dirr, MA and KS Warren. 2019. Ailanthus altissima In: The Tree Book: Superior Selections for Landscapes, Streetscapes, and Gardens. Portland, OR: Timber Press. 154.
- Finley, J. 2018. Tree-of-heaven and the spotted lanternfly: two invasive species to watch. In: Center for Private Forest News (Online). Penn State University, Department of Ecosystem Science and Management. 7/30/2019.
- Fryer, JL. 2010. Aillanthus altissima. In: Fire Effects Information System (Online). U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory.
- Gover, A, Johnson, J, Lloyd, K and J Sellmer. 2008. Invasive plant species management quicksheet 5: tree-of-heaven (Ailanthus altissima). Penn State University, Department of Horticulture. 7/30/2019.
- New York State Integrated Pest Management Program. 2019. Spotted lanternfly: known distribution. 7/30/2019.
- Wickert, KL, O’Neal, ES, Davis, DD, and MT Kasson. 2017. Seed production, viability, and reproductive limits of the invasive Ailanthus altissima (tree-of-heaven) within invaded environments. Forests. 8: 226.
Photo: Richard Gardner, via bugwood.org