Triumph™ Elm (Ulmus 'Morton Glossy')

Triumph™ (cultivar name 'Morton Glossy') is an Asian elm hybrid developed at the Morton Arboretum. It is among the most DED-resistant elms in commercial production and is distinguished from other Morton releases by its notably glossy dark-green foliage.

Origin

Triumph™ was developed at the Morton Arboretum as part of George Ware's long-term elm breeding program. The cultivar derives from a complex hybrid background — among its parents are 'Vanguard' (Ulmus japonica) and Accolade™ (Ulmus 'Morton'). The selection was made for combined disease resistance, glossy foliage, and improved street-tree form.

Commercial release came through Chicagoland Grows in 2005, with broader distribution following over the subsequent decade.

Identification

Form: Upright oval, more symmetrical and somewhat narrower than Accolade™

Mature size: 55–60 feet tall, 35–45 foot crown spread

Leaves: Distinctly glossy dark green; 2–4 inches, oval, double-serrated, asymmetric base

Fall color: Yellow

Bark: Gray-brown, becoming scaly with age

Growth rate: Fast

Hardiness and adaptability

USDA hardiness zones: 4–7

Site preferences: Tolerates urban soils, compaction, salt, and a range of pH

Stress tolerance: Drought-tolerant; performs well in heat

Dutch Elm Disease resistance

Triumph™ demonstrates excellent DED resistance, consistent with its Asian parentage and the resistance background of Accolade™. In National Elm Trial evaluations, the cultivar showed near-zero disease incidence over the 10-year study period (Griffin et al. 2017).

Triumph™ is also resistant to elm yellows phytoplasma.

Landscape uses

Street trees in urban environments throughout the central and eastern United States

Park, campus, and institutional plantings

Plantings where glossier foliage and a more uniform crown are aesthetically preferred over Accolade™

Mixed cultivar palettes for genetic diversity

Limitations

Hardiness limited to zone 4 minimum

Performance in hot southern climates (zone 8+) is variable

Like other Asian hybrids, leaf and bark aesthetics differ from American elm

Availability has improved since the mid-2010s but may still vary regionally

Similar cultivars

Accolade™ — sibling Morton release with broader form, similarly high resistance

Allee® — Chinese elm cultivar

Athena® — Chinese elm cultivar with more compact form

Related pages

What Cultivars Are Resistant to Dutch Elm Disease?

Disease-Resistant Varieties Guide

Elm Species: A Complete Guide

References

Ware, G. H. (1995). "Little-known elms from China: landscape tree possibilities." Journal of Arboriculture, 21(6), 284–288.

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.

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.