Slippery elm (Ulmus rubra) is a medium tall deciduous tree . Leaves are large, thick, very rough above, abruptly pointed, and folded up along the mid-vein. Twigs are relatively stout and light brown with large, oval, blunt, dark brown buds. Mature bark is dark red-brown in long scaly plates. Flowers are short-stalked and emerge very early in spring before leaves. Fruit is pale yellow-green, often darker in the center and ripens as leaves unfold. From central and eastern North America. Named rubra in 1793 for its rusty-red buds (easily recognized in winter by the iridescent red hairs on twigs and buds). Not commonly cultivated, but once highly valued for the sweet, slippery inner bark that was used as medicine. The inner bark exudes a slick gel or mucilage (hence the common name) used to treat coughs. Distinguished from American elm by short stalked flowers and samaras as well as downy twigs. Its common name (red) comes from its red hairy buds and it slimy red mucilaginous inner bark (slippery). The genus name comes from the Latin name of this tree.
Common name: Slippery Elm, Red Ulm, Soft Ulm, Ulmus fulva
Scientific Name (family and order): Ulmus rubra Muhl. (Ulmaceae, Rosales)
Species Origin: Central Southern USA
New Jersey Status: USDA Native
Habit: Straight trunk; 50 – 80’ tall x 30 -50’ wide: bole 1 – 2 ½” diameter. Overall shape less graceful than the American Elm.
Habitat: Zone 3 – 9.
Trunk/Stem: Bark rough gray to reddish brown; plates separated by irregular furrows. Lacks the white patches of American Elm. Twigs gray brown with rough sandy hairs when young; branches become hairless.
Leaves: Deciduous, Simple, Alternate. The upper leaf surface is very sandpaper rough 5 -7‘ long x 2-3 “ wide. Elliptic ovate or obovate with abruptly pointed tip. Rounded asymmetric base. Margins coarsely double-toothed.
Flowers: Perfect. Flowers darkish red; each flower on a short stalk. Flowers appear before leaves in spring.
Fruits and seeds: Rounded samara, ½ – ¾ “ wide, slightly notched at the tip, yellowish in pedicillated cluster. This samara is NOT hairy on its margins like other native elms.