Disease-Resistant Elm Varieties Guide

Disease-Resistant Elm Varieties

After a century of Dutch Elm Disease losses, resistant elms exist, perform well in field trials, and are commercially available. Modern cultivars combine the classic vase shape and shade canopy of the American elm with disease resistance bred in from Asian species. This guide describes the major cultivar groups and the trade-offs among them.

Three families of resistant elms

Resistant elm cultivars fall into three groups:

American elm selections — pure Ulmus americana trees descended from rare survivors that withstood the original epidemic. Examples: 'Princeton', 'Valley Forge', 'New Harmony', 'Jefferson'.

Asian elm hybrids — crosses between Asian species (typically Japanese, Siberian, or Wilson's elm) that combine high resistance with cold-hardiness or specific landscape forms. Examples: 'Accolade™' (Morton), 'Triumph™', 'Allee®', 'Athena™'.

European selections — derived from breeding programs in the Netherlands and the UK using surviving European stock. Examples: 'Columella', 'Groeneveld', 'Rebella'.

For a side-by-side cultivar comparison with growth habit, hardiness, and resistance ratings, see What Cultivars Are Resistant to Dutch Elm Disease?.

How resistance actually works

No elm is fully immune to Ophiostoma novo-ulmi. Resistant cultivars survive infection through one or more of:

Smaller xylem vessels that limit how far the fungus can spread before encountering tylose barriers

Faster compartmentalization — the tree walls off infected tissue more quickly

Antifungal phenolics in the heartwood that inhibit fungal growth

Reduced beetle attractiveness in some Asian-derived hybrids

The trade-off: resistance is a continuum, not a switch. Even the best-rated cultivars can succumb under heavy disease pressure if combined with drought, root damage, or other stresses. See Are There Trees Resistant To Dutch Elm Disease? for more on the biology of resistance.

Choosing the right cultivar

Match the cultivar to the planting site:

Site need | Best matches
Classic American vase shape | 'Princeton', 'Valley Forge', 'New Harmony'
Cold-hardy (USDA zones 3–4) | 'St. Croix', 'Prairie Expedition', 'Discovery'
Compact urban form | 'Accolade™', 'Triumph™', 'Allee®'
Tight columnar form | 'Columella'
Hot/dry climates | Ulmus parvifolia (Chinese elm) cultivars

For street tree plantings, also consider:

Mature canopy width vs. available rooting space

Salt tolerance (most resistant elms are moderately tolerant, but check)

Litter (some elms drop heavy seed loads in spring)

Genetic diversity — plant at least 3–4 different cultivars along any given block to avoid monoculture vulnerability

Sourcing resistant cultivars

Resistant elm cultivars are widely available through specialty nurseries and an increasing number of mainstream growers. Look for:

Verified cultivar identity (genetics, not just label)

Stock grown locally or in a similar hardiness zone

Bare-root or ball-and-burlap stock with good root architecture

Cooperative buying through municipal forestry programs, where available

The National Elm Trial network and regional arboreta maintain ongoing performance data across regions; the nearest land-grant university extension service is the standard source for region-specific cultivar recommendations.

What resistance does not mean

A few things to keep in mind:

Resistant elms can still harbor and transmit the fungus to nearby susceptible trees

They are not exempt from quarantine rules on moving elm wood

Long-term resistance durability depends on the pathogen not evolving — continued monitoring matters

Resistance does not eliminate the need for preventive sanitation and good site management

For the long-term outlook on elms as a species, see Will Dutch Elm Disease Make Elms Extinct?.

Topics in this cluster

Are There Trees Resistant To Dutch Elm Disease?

What Cultivars Are Resistant to Dutch Elm Disease?

What are Dutch Elm trees?

References

Townsend, A. M. (2000). "USDA genetic improvement of urban trees." Acta Horticulturae, 496, 87–95.

Smalley, E. B., & Guries, R. P. (1993). "Breeding elms for resistance to Dutch elm disease." Annual Review of Phytopathology, 31, 325–354.

Santamour, F. S., & Bentz, S. E. (1995). "Updated checklist of elm (Ulmus) cultivars for use in North America." Journal of Arboriculture, 21(3), 122–131.

Griffin, J. J., Jacobi, W. R., McPherson, E. G., et al. (2017). "Ten-year performance of the United States National Elm Trial." Arboriculture & Urban Forestry, 43(3), 107–120.