Elm Species: A Complete Guide
The genus Ulmus contains about 40 species of deciduous and semi-deciduous trees native to the northern hemisphere. Roughly half are economically or ecologically significant; this guide covers the species most relevant to landscape planting, urban forestry, and Dutch Elm Disease management.
For quick visual identification cues, see How to Identify an Elm Tree. For disease-resistant cultivars within these species, see What Cultivars Are Resistant to Dutch Elm Disease?.
North American native species
| Species | Common name | Range | DED susceptibility |
|---|---|---|---|
| Ulmus americana | American elm | E. & C. North America | High |
| Ulmus rubra | Slippery elm (red elm) | E. North America | Moderate |
| Ulmus thomasii | Rock elm (cork elm) | NE United States, S. Canada | Moderate-high |
| Ulmus alata | Winged elm | SE United States | Low-moderate |
| Ulmus crassifolia | Cedar elm | S. United States | Low-moderate |
| Ulmus serotina | September elm | SE United States | Moderate |
American elm dominated the urban canopy of the eastern half of the continent before DED. The southern and western native species (winged, cedar) suffered less because their ranges had less overlap with elm bark beetle habitat and they have somewhat lower susceptibility.
European species
| Species | Common name | Range | DED susceptibility |
|---|---|---|---|
| Ulmus glabra | Wych elm (Scots elm) | N. & C. Europe, UK | High |
| Ulmus minor / procera | English elm / field elm | UK, W. & C. Europe | Very high |
| Ulmus laevis | European white elm / fluttering elm | C. & E. Europe | Moderate |
European elms suffered the first wave of DED in the 1920s and the more virulent Ophiostoma novo-ulmi wave starting in the 1940s. The British countryside lost an estimated 25 million elms to the disease.
Asian species
| Species | Common name | Range | DED susceptibility |
|---|---|---|---|
| Ulmus parvifolia | Chinese elm / lacebark elm | China, Korea, Japan | Low |
| Ulmus pumila | Siberian elm | C. & E. Asia | Low |
| Ulmus japonica | Japanese elm | E. Asia | Low-moderate |
| Ulmus wilsoniana | Wilson's elm | China | Low |
| Ulmus davidiana | David elm | NE Asia | Low |
Asian species evolved in regions where related Ophiostoma species are endemic and have largely retained resistance. They are the primary genetic source for modern resistant elm cultivars.
Hybrid cultivars
Most commercially available DED-resistant elms are hybrids combining American or European elm form with Asian elm resistance. See What Cultivars Are Resistant to Dutch Elm Disease? for individual cultivar profiles.
Commonly confused species
A few species cause persistent identification confusion:
- Chinese elm vs Siberian elm: Often mislabeled at nurseries. Chinese elm (U. parvifolia) has small leaves, mottled lacebark, and exfoliating bark; Siberian elm (U. pumila) has larger leaves, deeply furrowed bark, and is considered invasive in much of North America.
- Slippery elm vs American elm: Similar leaves and bark; slippery elm has a reddish, mucilaginous inner bark and rougher upper leaf surface.
- English elm vs field elm: Sometimes treated as separate species, sometimes as one (U. minor sensu lato). The classic British hedgerow "English elm" is genetically distinct but its taxonomic placement remains debated.
Topics in this cluster
- How to Identify an Elm Tree
- American Elm (Ulmus americana)
- English Elm (Ulmus minor)
- Wych Elm (Ulmus glabra)
- Chinese Elm (Ulmus parvifolia)
- Siberian Elm (Ulmus pumila)
- Slippery Elm (Ulmus rubra)
Related pages
- What are Dutch Elm trees? — overview of the genus
- Disease Biology & Causes — how the disease attacks these species
- Disease-Resistant Varieties Guide
References
- Sherman-Broyles, S. L. (1997). "Ulmaceae". In Flora of North America, vol. 3. Oxford University Press.
- Richens, R. H. (1983). Elm. Cambridge University Press.
- Heybroek, H. M., Goudzwaard, L., & Kaljee, H. (2009). Iep of olm: Karakterboom van de Lage Landen. KNNV Uitgeverij.