Description

Ulmus – Elm

This genus is comprised of 45 deciduous, rarely semi-evergreen trees and very rarely shrubs.  Most elms are large limbed trees forming a domed crown with furrowed or fissured gray bark.  There found natural occurring in woodland, thickets, and hedgerows in the northern hemisphere and Siberia to Indonesia, Mexico to Japan.  They have alternate, ovate to elliptic, egg shaped or rounded leaves with prominent, parallel lateral veins and may be single or double toothed margins and with unequally sized bases. The leaves usually color to yellow in autumn.  Cluster of tiny, bell shaped flowers, each with 4-9 segments joined at the bases, are usually produced from auxiliary buds in spring, but sometimes from leafy buds in autumn, they are quickly followed by green to brown, rounded to elliptic, membranous wing seed capsules.  Cultivated for their habit and foliage, elms’ are mainly grown as specimen trees.  Ulmus x hollandica ‘Jacqueline Hillier’ is suitable for shrub border and for hedging.

In areas free of Dutch elm disease grow in any well-drained soil in full sun or partial shade.  Zelkovas are good substitutes where Dutch elm is prevalent.

Prone to Dutch elm disease caused by the fungus Ophiostoma Ulmi spread by bark beetles and natural grafts, has destroyed hundred of thousands of American elms.  There has been recent breeding between European and Asiatic species that are slowly showing more resistant to the disease. They are also prone to Borers, Beetles, Caterpillars, mealy bugs, scale insects, leaf hoopers, mushroom root rot, dieback, canker, Verticillium wilt, wood rot, lepidopteran larvae, hepialid moth, phloem necrosis, and elm yellows.

Ulmus parvifolia ‘Emerald Isle’ – Chinese Elm – Lacebark Elm –This spreading, deciduous or semi evergreen rounded crown tree is found naturally occurring in China, North Korea, Vietnam and Japan and grows 30’ feet tall with a spread of 55’ feet wide.  It bears smooth flaking bark mottled with dark gray, reddish-brown and cream.  It produces elliptic single toothed, leathery, glossy, dark green leaves, to 2 ½” long with bases of almost equal size with matted hair beneath, that may develop yellow or red tones in late autumn or early winter.  Tiny red flowers are produced from late summer to autumn, winged green fruit follows them, 3/8” across, in late autumn.  Tolerant of urban soils and highly resistant to Dutch Elm disease.

Zones 5-9