Elm, a large, ornamental shade tree. There are about 25 species in the elm family. Elms grow in the north temperate regions of America, and in Africa, Asia, and Europe. Elm wood is strong, hard, and coarse-grained. It is used in making furniture, tool handles, wheels, and woodenware.

The elmThe elm is a large, ornamental shade tree.

Although the elm is a hardy tree, it is damaged by insects such as aphids, cankerworms, elm-leaf beetles, and bark beetles. The most serious affliction is Dutch elm disease, caused by a fungus transmitted by bark beetles.

The American elm may grow to a height of 120 feet (37 m). The branches of this species spread upward and outward from the main trunk. The bark is light gray and coarse. The oval leaves, three to seven inches (7.5-18 cm) long, grow from short stalks. Tiny flowers appear in drooping clusters before the leaves open. The flat, elliptical fruits, each carrying one seed, have thin, papery margins that aid in seed dispersal by enabling the fruits to glide through the air when they fall. The American elm is found throughout most of the United States.

The English elm is more globular in shape than the American elm. It can grow to a height of 130 feet (40 m). Its leaves are two to four inches (5 to 10 cm) long, and its fruits are similar to those of the American elm. The English elm is native to southern England, and is also found in northern Europe and the northeastern United States.

The urban elm is a hybrid species which is resistant to Dutch elm disease. It has replaced the American elm in many suburban areas of the United States.

Elms belong to the elm family, Ulmaceae. The American elm is Ulmus americana; the English elm, U. procera; the urban elm, U. urbana. Other North American elms are the winged, or wahoo, elm, U. alata; the cedar elm, U. crassifolia; the slippery elm, U. rubra; the September elm, U. serotina; and the rock, or cork, elm, U. thomasii.