Ulmus pumila
Ulmus rubra
Asiatic elm, dwarf elm, Siberian elm
orme rouge, slippery elm
gray to brown, deeply furrowed with interlacing ridges.
brown to red, deeply and irregularly furrowed.
not winged;
twigs gray-brown, pubescent.
spreading;
twigs gray, densely pubescent when young, glabrous with age.
dark brown, ovoid, glabrous;
scales light brown, shiny, glabrous to slightly pubescent.
obtuse;
scales red, margins red-tomentose.
blade narrowly elliptic to lanceolate, 2-6.5 × 2-3.5 cm, base generally not oblique, margins singly serrate, apex acute;
surfaces abaxially with some pubescence in axils of veins, adaxially glabrous;
lateral veins forking to 3 times per side.
blade obovate to ovate, 8-16 × 5-7.5 cm, base oblique, margins doubly serrate in distal 1/2-3/4, singly serrate proximally, basal teeth 6 or fewer, rounded, less distinct, apex acuminate;
surfaces abaxially tomentose, dense tufts of white hair in axils of major veins, adaxially harshly scabrous, trichomes pointed toward apex, margins ciliate.
tightly clustered fascicles, 6-15-flowered, 0.5 cm, flowers and fruits not pendulous, sessile.
dense fascicles less than 2.5 cm, 8-20-flowered, flowers and fruits not pendulous, subsessile;
pedicel 1-2 mm.
calyx shallowly lobed, lobes 4-5, glabrous;
stamens 4-8;
anthers brownish red;
stigmas green, lobes exserted.
calyx green to reddish, shallowly lobed, lobes 5-9, reddish pubescent;
stamens 5-9;
anthers reddish;
stigmas exserted, pink reddish.
thickened, not inflated.
thickened, not inflated.
brittle.
soft.
yellow-cream, orbiculate, 10-14 mm diam., broadly winged, glabrous, tip notched 1/3-1/2 its length.
yellow to cream, suborbiculate, 12-18 mm diam., broadly winged, samaras pubescent on body only, rusty-tomentose, margins glabrous.
= 28.
= 28.
Ulmus pumila
Ulmus rubra
Ulmus pumila probably occurs in Vermont and West Virginia, but it has not been documented for those states.
Planted for quick-growing windbreaks, Ulmus pumila has weak wood, and its branches break easily in mature trees. It is easily distinguished from other North American elms by its singly serrate leaf margins. Ulmus pumila is similar to U. parvifolia Jacquin with its small, singly serrate leaves. Ulmus parvifolia, however, has smooth bark that sheds from tan to orange, and it flowers and sets fruit in the fall.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Scabrous-leaved Ulmus rubra is often confused with U. americana. Where ranges coincide, U. rubra may freely intergrade with Ulmus pumila Linnaeus, a widely introduced species.
The red-rust, mucilaginous inner bark of Ulmus rubra is distinctive; its sticky slime gives this tree its common name of slippery elm. Native American tribes used Ulmus rubra for a wide variety of medicinal purposes, including inducing labor, soothing stomach and bowels, treating dysentary, coughs, colds, and catarrhs, dressing burns and sores, and as a laxative (D. E. Moerman 1986). Various preparations utilizing it are still marketed.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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- WildflowerSearch
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- USDA Plants Database
- LBJ Wildflower Center
- SEINet
- Plants of the World Online
- Encyclopedia of Life
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