Plant Family: Ulmaceae
Growth Form: Medium-sized to potentially a large tree with an attractive vase-like form.
Leaves / Buds: Alternate, simple, elliptic, margins double-toothed, bases uneven, 10 – 15 cm long; with 1 or 2 veins that fork near the margins; buds are brown and smooth.
Bark: Gray, deeply furrowed in a cross-hatched pattern.
Flowers: Small and inconspicuous, greenish-yellow, in sparse clusters, April to May.
Fruits: Oval, flattened samaras with deeply notched tips and a fringe of hairs on the margins; May to June.
Habitat: Floodplains, low damp woods, field edges, sometimes on upland sites.
Range: Throughout eastern North America, west to the Great Plains.
Similar Species: Slippery Elm has 2 to 6 veins that fork near the margins, the leaf buds are hairy, and there are soft hairs only on the central portion of the samaras, not the margins.
Comments: American Elm was formerly much more common and widely planted as a street tree. Dutch elm disease, introduced from Europe in the 1920s, and caused by fungi (Ophiostoma spp.) that are vectored by bark beetles, has severely reduced its numbers. Small to medium-sized trees are still widespread, but only a few large trees remain. There are ongoing efforts to develop disease resistant cultivars. American Elm is the state tree of Massachusetts and North Dakota.
