Common Name: Siberian elm
Scientific name: Ulmus pumila
Identification: Siberian elm is a large fast-growing deciduous tree, reaching up to 50’ tall with a vase-shaped to rounded crown up to 40’ wide at maturity. It can be much shorter and shrubbier under difficult growing conditions. The leaves alternate and are elliptical in shape with a pointed tip. Leaves are ¾-3” long, ⅓-1” wide, and are even or nearly even at the base on each side of the leaf stem. They are dark green on the top surface, smooth on both sides, and the leaf edges are singly toothed. The flowers are borne in small red tinged clusters in early spring, before leaves emerge. Individual flowers are about ⅛” across and are without petals. Seeds are borne in clusters of round, flat, papery samaras, ½” in diameter, which turn from light green to light brown as they ripen, falling from trees in late spring. Each samara contains one seed. (Hilty 2017)
Look-alikes: Siberian elm is somewhat similar to American elm (U. americana), slippery elm (U. rubra) and rock elm (U. thomasii), all of which are native to the Great Lakes region. The leaves of American and slippery elm are double or more the size of the leaves of Siberian elm, and are also notably uneven at the leaf base. Rock elm leaves are similar in size and shape to Siberian elm, but its older bark is distinctly ridged and corky, its seeds are hairy, and its crown is narrower than Siberian elm. Rock elm is also quite rare in much of its range. All of the native elms have double toothed leaf edges (the large teeth each have small, finer teeth), while the edges of Siberian elm leaves are singly toothed.
Siberian elm is most similar in appearance to the exotic ornamental lacebark elm (U. parviflora), which also has small leaves that are almost even at the base. Lacebark elm leaves are usually glossier on the top surface and more leathery in texture than Siberian elm. Lacebark elm flowers in the fall, not the spring. Finally, mature bark of lacebark elm has a distinct, lacey pattern, while Siberian elm bark has vertical ridges.
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Siberian elm is reported occasionally throughout the Great Lakes Basin. It occurs from coast to coast and has been verified in 45 of the lower 48 states and six Canadian provinces. In the U.S., it appears to be most frequently invasive in the arid southwest. Siberian elm is described by USDA as being hardy to -38 degrees Fahrenheit (Zone 3a), which has contributed to its wide distribution.
Additional invasive species distribution data for specific Great Lakes jurisdictions is available via:
- Midwest Invasive Species Information Network (Michigan)
- iMapInvasives (New York and Pennsylvania)
- EDDMapS Ontario
The seeds of Siberian elm are primarily spread by wind and germinate rapidly under suitable conditions.
Siberian elm frequently occurs in sunny, disturbed settings with poor soils, including old fields, pastures, riparian areas, and transport and utility rights-of-way. It can also invade prairies, grasslands, and savannas, including those with sandy soils. Siberian elm’s shade intolerance makes invasion of intact forests unlikely.
Siberian elm’s fast rate of growth, high production of seed, and high rate of seed germination in favorable conditions can allow it to become dominant in disturbed and open habitats. It can quickly shade out native species and utilize available water in dry conditions. The leaf litter produced by Siberian elm may decrease germination and growth of competing species (Pérez-Corona 2013).
Siberian elm has been found to hybridize extensively with slippery elm in the Midwest. It is theorized that the introduction of the native tree genes is allowing Siberian elm hybrids to colonize areas with high soil moisture, such as streambanks and wetland edges, where the species ordinarily would not grow (Zalapa et al. 2010). Over generations, hybridization favors the proliferation of Siberian elm genes over the native species, potentially threatening the future of slippery elm where the species ranges overlap (Zalapa et al. 2009).
Siberian elm was introduced to various parts of the U.S. from Northern China and Eastern Siberia beginning in the mid-1800s. Initially, it was primarily used as a windbreak between agricultural fields due during the Dust Bowl era to its fast growth and ability to withstand dry conditions in poor soils. It was later adapted to urban use as an alternative to native elms due to its Dutch elm disease resistance (Dirr 1998).
Although still available to a minor degree as a windbreak, Siberian elm has largely lost favor with commercial growers due to its invasiveness, tendency to incur storm damage, and susceptibility to elm leaf beetles. Its main utility is likely to remain as a genetic source of Dutch elm disease resistance for elm hybrids (Dirr and Warren 2019).
Please see our Landscape Alternatives pages for more information about how the WIGL Collaborative selected alternatives.
| Alternatives for Siberian Elm
Common name (Latin name) |
Large shade tree (>40ft tall at maturity) |
Drought tolerant | Fast growing |
| American elm (Ulmus americana) Dutch elm disease resistant cultivars only (e.g., ‘Jefferson,’ ‘Lewis & Clark’ PRAIRIE EXPEDITION®, ‘Valley Forge’) |
✔ | ✔ | ✔ |
| Ginkgo (Ginkgo biloba) Male cultivars (many) |
✔ | ✔ | |
| Exotic elm hybrids (Ulmus x.) ‘Morton’ ACCOLADE®, ‘Patriot,’ ‘Regal,’ ‘Morton Glossy’ TRIUMPH™ |
✔ | ~ | ✔ |
~ = trait is somewhat present but not as pronounced as in check-marked examples
Green = native to part of the Great Lakes Basin
Blue = not native but not invasive
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 Siberian elm. 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.
Timing and spread concerns: Early detection is an advantage in managing any invasive species. Whenever possible, plants should be controlled before they begin producing seed (~10 years of age for Siberian elm). If control is undertaken when seed is present, it is best not to remove the plants from the site to avoid spreading seed.
Physical control: Small seedlings can be pulled easily from moist soil, and juvenile trees can be pulled using equipment. Girdling may be the most cost effective way to treat mature trees, and may be suitable where use of herbicide is not consistent with site goals. Siberian elms should be girdled (a 3-4” strip of bark removed) in late spring to mid-summer. Care should be taken to remove all outer and inner bark from the girdled strip, but not to damage the inner wood, which can trigger sprouting. Top-killing methods such as mowing or felling can be used to prevent maturation but will not provide long-term control of juvenile plants. In fire adapted natural communities (prairies, grasslands, savannas, etc.), a regular prescribed fire regime can prevent Siberian elm seedlings from maturing and spreading seed.
Chemical control and combined approaches: Foliar, cut stump, basal bark, and application of herbicide to a girdle are effective on this species. Foliar applications should only be conducted when plants are fully leafed out and are likely restricted to sites with few desirable plants. Basal bark treatment can be used on trees of intermediate size (<6” in diameter at breast height) during most times of the year, avoiding early spring. For large trees, cut stump treatment or application of herbicide to a girdle are most effective. Girdle treatment should be done in late spring to mid-summer while cut stump can be during most of the year, avoiding early spring.
With any treatment it will be necessary to monitor for and treat regrowth and new seedlings.
Resources on management of Siberian elm:
- Dirr, MA. 1998. Ulmus pumila In: Manual of Woody Landscape Plants, Fifth Edition. Champlain, IL: Stipes Publishing. 1047-1048.
- Dirr, MA and KS Warren. 2019. Ulmus pumila In: The Tree Book: Superior Selections for Landscapes, Streetscapes, and Gardens. Portland, OR: Timber Press. 897.
- Hilty, J. 2017. Siberian elm In: Illinois Wildflowers. 9/20/2019.
- Pérez-Corona, ME, de las Heras, P, and BR Vázquez de Aldana. 2013. Allelopathic potential of invasive Ulmus pumila on understory plants. Allelopathy Journal. 32: 101-112.
- Zalapa, JE, Burnet, J, and RP Guries. 2009. Patterns of hybridization and introgression between invasive Ulmus pumila (Ulmaceae) and native U. rubra. American Journal of Botany. 96(6): 1116-1128.
- Zalapa, JE, Burnet, J, and RP Guries. 2010. The extent of hybridization and its impact on the genetic diversity and population structure of an invasive tree, Ulmus pumila (Ulmaceae). Evolutionary Applications. 3(2): 157-168.
Header Photo: Matt Lavin, under Creative Commons license, via flickr.com
