elm

Any of about 18 species of forest and ornamental shade trees that make up the genus Ulmus (family Ulmaceae), native mostly to northern temperate areas. Many are grown for their height and attractive foliage. The leaves are doubly toothed and often lopsided at the base. The flowers, which lack petals, appear before the leaves and are borne in clusters. Seeds are borne in a samara (dry, winged fruit). The American elm (U. americana) has dark gray, ridged bark and elliptical leaves. Many species are susceptible to Dutch elm disease. Elm wood is important for boats and farm buildings because it is durable in water; it is also used for furniture. See also slippery elm.

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