Description

This tree grows quickly when young to form a broad, upright, vase-shape. American Elms can grow 80 to 100 feet high and 60 to 120 feet wide. Trunks on older trees historically reached seven feet across.  The leaves are alternate and simple.  Their margins are double serrate, with the shape of the leaf being oblong and ovate.  The venation on the leaf is pinnate. The leaves are approximately six inches long and are dark green until autumn, when they turn yellow and begin to fall.  In the early spring before the leaves appear, small green flowers appear on the stalks.  The seedpods which soon form are green and round and approximately 0.5-1.0 inch long. Trees must be at least fifteen years old before they can bear seed, but bear seeds prolifically afterwards.    

Uses

American Elm trees were once a very popular and long-lived (>300 years) ornamental tree.  They were widely planted for shade and as a street tree because of their tolerance for urban conditions.  Unfortunately, the trees have suffered a dramatic decline after the introduction of a non-native fungus called Dutch elm disease that is spread by a bark beetle.  The wood of the American Elm is quite hard, which made it a valuable timber tree.  It was used for lumber, furniture, and veneer.  Historically, many Native American tribes made canoes from American Elm trunks.  Early settlers would steam the wood, to allow it to be bent to make barrels and wheel hoops.  It was also commonly used for the rockers on rocking chairs.  American Elm numbers are greatly reduced, and what wood is available now is used in the production of furniture.

Cultivation

Prior to its decline, the American Elm was grown successfully in urban areas where air pollution, compacted soil, drought, and poor drainage are common. In a natural setting, the American Elm grows in a variety of light conditions.  It is also tolerant of clay, loam, sand, and a wide variety of soil pH.  It also tolerates extended flooding. However, American Elm should be grown in full sun on well-drained, rich soil to avoid disease.  Any trees planted should be monitored for symptoms of Dutch elm disease.

References

Gilman, E.F., & Watson, D.G. (1994).  American Elm (ulmus americana) fact sheet.  Retrieved    from http://hort.ufl.edu/database/documents/pdf/tree_fact_sheets/ulmamea.pdf