Ulmus americana, the American Elm, is a large deciduous tree with the vase shaped crown the species is known for. Heavy limbs sweep up and outward before arching over at the tips. The leaves are broad, serrated and rough to the touch, mid green through summer and a clear yellow in autumn.
Full sun and deep, moisture holding soil bring the best growth, around 60 to 90 centimetres a year. It handles a wide range of soils once established, along with frost, wind and compacted urban ground. Cool temperate and temperate districts suit it, through Victoria, Tasmania, the ACT and southern New South Wales.
Given 20 to 30 metres of height and 15 to 20 metres of spread at maturity, this is a tree for parks, broad verges and large rural gardens. It is the classic avenue elm, casting deep summer shade and letting winter sun through. Plant it where the canopy will never need cutting back.
Frequently Asked Questions
About American Elm
What is an American Elm?
Ulmus americana is a large deciduous tree from eastern North America, grown for the arching vase shaped crown that made it the classic avenue elm. Heavy limbs rise and then bend outward at the tips. The broad serrated leaves are rough textured, mid green through summer and clear yellow in autumn.
How big does an American Elm grow?
Mature trees reach roughly 20 to 30 metres tall with a spread of 15 to 20 metres. Growth is upward and then outward, so the eventual footprint is wide. It is a tree for parks, wide verges, school grounds and rural properties rather than an average suburban backyard or courtyard.
How fast does it grow?
Growth is moderate to fast, around 60 to 90 centimetres a year in good soil with reliable moisture. Young trees put on height quickly, and the characteristic vase shape develops over the following ten to fifteen years. Growth slows noticeably on dry or compacted ground, so soil preparation pays off.
Is American Elm frost tolerant?
Yes, comfortably. It is a cold climate tree that handles hard frost and cold winters without damage, which makes it well suited to Victoria, Tasmania, the ACT and the tablelands of New South Wales. It also copes with wind exposure. Hot, humid subtropical conditions are the least suitable for it.
Is it deciduous?
Yes. The leaves yellow and drop through autumn and the tree stands bare over winter, showing off the branch architecture, then leafs out in spring. Small reddish flowers appear on bare wood in late winter and early spring ahead of the foliage, followed by papery winged seeds.
Is Dutch elm disease a problem in Australia?
Australia is one of the few places in the world free of Dutch elm disease, and strict quarantine keeps it that way. The pest you will actually meet is elm leaf beetle, which skeletonises foliage in Victoria, South Australia, Tasmania and parts of New South Wales. It is managed by trunk injection or soil treatment.
How do I care for an American Elm?
Water deeply through the first few summers and mulch out towards the drip line. Prune in late winter, removing crossing limbs and narrow forks early so the mature canopy is structurally sound. Monitor for elm leaf beetle from late spring and treat if damage builds. Rub suckers off the base as they appear.