Lacebark Elm or Chinese Elm

(Ulmaceae - Elm Family)

Form

• large shade tree
• maturing at about 50' tall by 60' wide
• upright oval growth habit in youth, becoming spreading, rounded, or broad-vased with age
• medium growth rate

Culture

• full sun to partial sun
• best performance occurs in full sun in moist, well-drained soils, but it is very urban tolerant, including adaptability to poor soils, dry soils, soils of various pH, heat, and drought
• propagated by seeds or rooted stem cuttings
• Elm Family, with no disease or pest problems of ornamental significance, including its resistance to Dutch Elm Disease
• moderately available in ball and burlap form

Foliage

• dark green and shiny, alternate, elliptical to ovate, serrated, nearly symmetrical at the base, and unusually small for an elm (usually only 1.5" long)
• fall color is an excellent mixture of yellow, gold, orange, red, purple, and green, and coloring very late, in early- to mid-November

Flowers

• inflorescences open in August and early September, are greenish-yellow, occur in the leaf axils, and are noticeable but ornamentally insignificant, being rather small and hidden among the foliage

Fruits

• initial color of the fruits is a striking lime green, quickly maturing to a deep russet, both of which contrast well against the dark green, shiny foliage
• rapidly growing in September and maturing in October, with the small samaras notched at their apex and hangiing in clusters from the leaf axils

Twigs

• the mature first-year gray stems are very slender, slightly zig-zag, ultra-fine textured, and with very small Winter buds

Trunk

• usually single-trunked but branching at about five to eight feet off the ground into several co-dominant trunks the give the tree its spreading, rounded, or broad-vased growth habit
• trunk diameter at its base at maturity is three to four feet of caliper, which allows for a large surface area for the ornamental bark to be displayed upon, in addition to the several co-dominant trunks and many branches in the canopy
• young bark is a flaky brown-gray color, but mature bark is an exfoliating, mottled, and flaky combination of gray, green, orange, tan, and red-brown, and greatly increases in beauty with age

ID Summary

• a shade tree that is unique amongst Elms in its combination of fine-textured small foliage with nearly symmetrical bases, chartreuse inflorescences that bloom in late Summer, samara fruits that mature in early- to mid-Autumn, and ornamental mottled and flakey bark of various colors that add beauty to the spreading trunks

USAGE

Function

• shade or specimen tree, giving dappled shade in youth

Texture

• medium-fine texture in foliage and fine texure when bare
• open to average density in foliage but thick density when bare

Assets

• excellent fall color mixture that transitions very late in the landscape
• ornamental bark with age
• fine-textured Winter twigs that are semi-pendulous with age, and a broad-vased growth habit with large spreading trunks
• urban tolerant

Liabilities

• marginally hardy in severe zone 5 Winters

Habitat

• species form is generally hardy from zones 5 to 8 (cultivars range from a extra-hardy zone 4 to a tender zone 7 in terms of their northern-range cold hardiness)
• native to the Orient

SELECTIONS

Alternates

• large shade trees with semi-filtered shade, at least in youth (Betula nigra, Gleditsia triacanthos, Populus tremuloides, Robinia pseudoacacia, etc.)
• trees with ornamental bark (Acer griseum, Betula papyrifera, Fagus sylvatica, Syringa reticulata, Zelkova serrata, etc.)
• trees with fine-textured branching (Alnus glutinosa, Betula pendula, Carpinus caroliniana, Ostrya virginiana, Ulmus procera, etc.)
• shade tree members of the Elm Family that are resistant to Dutch Elm Disease and are of ornamental quality (Ulmus americana 'Delaware', Ulmus x 'Homestead', Ulmus x 'Pioneer', Ulmus x 'Regal', Ulmus x 'Urban', Zelkova serrata)

Variants

• the species form is still the predominate form available; however, a number of cultivars exist based upon superior growth rate, Summer foliage, fall color, ornamental bark, and variable growth habits, but none have yet become established in the nursery trade

NOTES

Translation

• Ulmus is the Latin name for Elm.
• parvifolia translates as "small foliaged", in reference to this species having a very small leaf for an Elm.

Purpose

• Lacebark Elm is the perhaps the best all-around Elm for its combination of clean foliage, fall color, and ornamental bark, while not being susceptible to Dutch Elm disease.

Summary

• Ulmus parvifolia is known as an unusual Elm that has excellent ornamental bark and mixed fall color that transitions very late, and also has excellent dark green shiny Summer foliage, flowering and fruiting late in the season, and a spreading habit from co-dominate trunks and semi-pendulous branchlets that provide filtered shade.