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| The elm family consists of about 15 genera which include 150 or more species of plants that are widely distributed through temperate and tropical forests of the world. 3 species of 2 genera are introduced below. |
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| Celtis laevigata
sugarberry |
Habit
The sugarberry is a medium-sized tree, 60-80 feet in height, 2-3 feet in diameter. It has a straight, short bole and an open crown of slender, spreading branches, and a spreading root system. Leaves Leaves are simple, alternate, and deciduous. The leaves are 2.5-5
inches long, 1-3 inches wide, oval to elliptical-shaped, tapering to an
acute apex. Leaf bases are wedge-shaped or asymmetrically rounded.
Leaf margins are entire or with a few teeth near the leaf apex. Leaf
surfaces are light green, smooth, or occasionally roughened above, paler
and smooth below. Petioles are slender and smooth, about 1/3 inch
long.
The twigs are slender, zigzagging, greenish brown to light reddish brown.
The pith is commonly chambered at the nodes, homogenous between the nodes.
The bark is gray-brown to silvery gray, featured with many characteristic
corky warts and ridges, particularly on the lower portions of the bole,
bark is scaly on old trees.
The sugarberry grows on stream banks, river bottoms, and moist alluvial
flats of clay and silt loam. It usually occurs as an occasional tree
in association with may species, most commonly with sweetgum, pecan hickory,
green ash, elms, overcup oak, water oak, and honeylocust. It is found
in the southeastern U.S. from coastal Virginia to eastern Texas, including
Florida and the Keys.
The wood of this tree is used for furniture and crating.
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| Ulmus alata
winged elm |
| Habit
The winged elm is a tree, 40-50 feet in height, 1-3 feet in diameter.
It has a short bole terminating into several ascending limbs with laterally
spreading branchlets, forming an oblong, nearly spherical crown.
Leaves are simple, alternate, and deciduous. The leaves are 1.5-3.5
inches long, 1-2 inches wide, oval to elliptical-shaped, tapering to an
acute apex. Leaf bases are unequally rounded or heart-shaped.
Leaf margins are coarsely doubly serrate. Leaf surfaces are dark
green and smooth above, paler and pubescent below. Petioles are short
and stout, about 1/3 inch long.
The twigs are slender, grayish-brown to reddish-brown, and glabrous
or pubescent. They are usually furnished with 2 corky wings or ridges,
which appear during either the first or second year.
The bark is light brownish-gray, divided into flat, superficially scaly
ridges by narrow, shallow fissures.
The winged elm is common throughout much of the south. It grows
well on dry, gravely soils at low elevations. It is less common near
streams and on alluvial flats or in swamps. It is found from southeastern
Virginia west through the lower Ohio River Valley and southern Missouri
to north-central Oklahoma; south to central Florida and eastern Texas.
Due to its rapid growth, pleasing habit, and relative freedom from disease
or insect pests, it is a favorite ornamental and street tree in many southern
communities. The inner bark is fibrous and was used in the past for
baling twine.
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| Ulmus americana
American elm |
| Habit
The American elm is a moderately large tree, 80-120 feet in height,
2-5 feet in diameter. It usually has a heavily buttressed bole that
divides several feet above the ground into a number of gracefully arching
limbs, forming an attractive, vase-like or spreading crown of pleasing
symmetry and beauty.
Leaves are simple, alternate, and deciduous. The leaves are 4-6
inches long, 2-3 inches wide, oval to elliptical-shaped, tapering to an
acute apex. Leaf bases are unequally rounded. Leaf margins
are coarsely doubly serrate. Leaf surfaces are dark green and smooth
above, paler and pubescent or rarely glabrous below. Petioles are
short and stout, about 1/4 inch long.
The twigs are slender, reddish-brown to dark brown, and glabrous or
sparsely pubescent.
The bark is ashy gray, divided into broad, flat-topped ridges by deep,
elliptical to diamond-shaped fissures.
The American elm is common on bottomlands, alluvial flats, margins of
stream, ponds, and lakes, and on moist fertile slopes and uplands in association
with other hardwoods. It is found from Newfoundland west through
southern Canada to Saskatchewan and the Rocky Mountains, south to central
Florida and eastern Texas.
The American elm is a favorite and highly prized ornamental street and
shade tree in many U.S. cities. The wood is very durable and is suited
for use in the manufacture of kitchenette furniture, flooring, baskets,
and woodenware. This species is threatened by Dutch elm disease.
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