American Elm (White Elm, Water Elm)
Kingdom: Plantae, Division: Tracheophyta, Class: Magnoliopsida, Order: Rosales, Family: Ulmaceae, Genus: Ulmus, Species: Ulmus americana · Ulmaceae (Elm family) · Simple, deciduous leaf
Species
Ulmus americana
Leaf Type
Simple, deciduous leaf
Family
Ulmaceae (Elm family)
Shape
Elliptical to ovate with an asymmetric (unequal) base
Size
Approximately 3 to 6 inches long and 1 to 3 inches wide, which is typical for a mature American Elm leaf
Margin
Doubly serrate (coarsely toothed with smaller teeth on the primary teeth)
Arrangement
Alternate
Rarity
Common, though wild populations have been significantly impacted by Dutch elm disease
Color & Pattern
Rich medium to dark green on the upper surface, slightly paler underneath. Turns a soft yellow in autumn. Colors are typical for a healthy mature summer leaf.
Venation Pattern
Pinnate with straight, prominent parallel veins branching from a central midrib
Texture & Surface
Rough and sandpapery to the touch (scabrous) on the upper surface, with some fine hairs along the veins underneath
Description
The American Elm is a majestic, large deciduous tree famous for its distinctive vase-like silhouette and arching canopy. It features dark gray bark with deep intersecting ridges, small inconspicuous flowers that bloom in early spring before leaves emerge, and papery winged seeds known as samaras.
Key Features
Unequal (asymmetric) leaf base where one side of the blade attaches lower on the petiole than the other, combined with a rough texture and doubly serrate margins
Habitat
Bottomland forests, floodplains, riverbanks, and moist rich soils, though highly adaptable to urban environments
Geographic Range
Native to eastern North America, ranging from Nova Scotia west to Alberta, and south to Florida and central Texas
Condition Notes
Good condition; the pressed and mounted herbarium specimen shows intact margins and clear venation with minimal degradation
Interesting Facts
Historically planted widely as a shade tree that created grand living arches over American streets, but populations were devastated by Dutch elm disease, a fungal pathogen spread by elm bark beetles
Medicinal & Uses
Native Americans used inner bark preparations for medicinal purposes to treat colds, coughs, and wounds. Valued historically for its tough, interlocking wood used in shipbuilding, furniture, and barrel making, and widely planted as a resilient urban street tree
Ecological Role
Provides vital nesting habitat and food for various birds and mammals, including caterpillars of several butterfly and moth species
Similar Species
Slippery Elm (Ulmus rubra), which has even rougher, larger leaves, and Wych Elm (Ulmus glabra). Can also be confused with some members of the Betulaceae family like Hornbeams, but the extremely asymmetric base is a giveaway for elms
Foraging Tips
Look for large vase-shaped trees near waterways or older neighborhoods. Leaves are easiest to study in spring and summer; check the base of the leaf blade for the classic lopsided attachment
Toxicity Warning
Non-toxic to humans and animals