SHADE TREES FOR THE SOUTHEAST

RALPH M. LINDGREN, R. P. TRUE, E. RICHARD TOOLE.

Residents of the Southeastern States have a wide choice of trees for shade and ornamental purposes. They also have a difficulty in making their selection, for their section has variables in climate and altitude and other conditions that do affect tree growth. (Florida alone, for example, can be subdivided into at least three distinct zones in which climate and commonly used plants are likely to differ a good deal from each other.)

Furthermore, certain local conditions may sometimes prevent the successful use of a species within the recognized geographic range of the Southeast. For these reasons, the list of trees we present is not expected to be entirely acceptable throughout the region or adequate for specific localities.

THE LIVE OAK, a tree of history and beauty, is long-lived and rather slow growing. It attains tremendous size with age. It branches low into massive and widespreading limbs, and forms a broad, dense, round-topped crown of dark, glossy, evergreen leaves. It resists storm damage, insects, and diseases; the costs of care and maintenance therefore are relatively low.

Propagation from seed or transplants is not difficult. The live oak is used widely where enough space is available on lawns and along driveways and roads. Severe freezes injure it, but it is considered satisfactory in such inland cities as Shreveport.

SOUTHERN MAGNOLIA, with its beautiful flowers and evergreen foliage, is a popular shade and ornamental tree. Rather large at maturity, it forms a broad, conical crown of pleasing symmetry. The thick, leathery leaves are dark, shining green above and rusty brown below. Large, fragrant, creamy-white flowers, mostly produced before July but sometimes continuing until November, are followed by purplish, conelike fruits. The tree is rather slow growing and long-lived, relatively free of pests, and tolerant of varying conditions except poor drainage. It usually is propagated from seed or pot-grown transplants. Adequate space is needed for best development, and it is often used singly on lawns. In the mountainous regions, severely cold weather may kill much of the foliage.

THE CAMPHOR-TREE is frequently planted in lawns and parks and along streets in many localities. It is a medium-sized, stout evergreen that forms a handsome, dense-topped crown. The leaves, shiny green above and silvery blue below, are strongly aromatic when crushed. The fruit, a small bluish-black drupe, often is abundant and occasionally is considered a nuisance. The tree is hardy but prefers a well-drained soil, and, except for thrips and scale, has few damaging pests.

It is propagated usually from seed or pot-grown transplants. Well-established trees resist temperatures of 15 F. without a great deal of injury.

THE WILLOW OAK is a rather large, long-lived, and fast-growing deciduous tree that develops a fairly short trunk in the open. It has a dense oval or round-topped crown. Slender branches with light-green, willowlike leaves give the tree a graceful appearance. Although growth is best in moist soils, it also thrives satisfactorily in rather dry situations.

It is easily transplanted, moderately storm-resistant, and, except for gall insects on branches and a leaf rust disease, is relatively free of pests. The leaf rust is seldom disfiguring, but it is the alternate stage of a serious canker disease of southern pines. Willow oak is used extensively as an attractive shade tree for wide streets and large lawns.

THE RED MAPLE has brilliant scarlet to orange autumnal coloring, which adds greatly to its ornamental value. It is medium to fairly large in size. Its branches develop low on the trunk to form a dense, narrow, oblong head, Conspicuous reddish flowers appear in early spring and are followed by scarlet fruits and attractive foliage.

The tree grows rapidly, is relatively short-lived, thrives satisfactorily on fairly varied sites, and is rather easily propagated and moderately resistant to pests. Although grown less often than many other trees, the red maple is not uncommon in the Southeast.

THE FLOWERING DOGWOOD is a native tree that is grown widely for its attractive flowers, red berries, and pleasing crown. It attains 40 feet and has spreading branches that form a low, fairly dense, rounded head. The small greenish-yellow flowers, produced in April, May, or June, are surrounded by four large, white bracts; pink forms occur also. Red fruit and autumnal leaf coloration add ornamental value.

The tree, rather slow growing and long-lived, is propagated with some difficulty from seed and cuttings. It has relatively few pests. It thrives in shaded or exposed places but prefers well-drained and fairly light soils. While not always easily established, it is useful around many homes.

THE SWEETGUM is a large and fast-growing tree with a pyramidal or oblong crown. The star-shaped, deciduous leaves develop brilliant autumn colors that range from yellow through orange to red and deep bronze. Corky ridges on some of the branches and the persistent spiny, fruiting balls are characteristically present. The tree is fairly long-lived, tolerant of different sites excepting poorly drained ones, and moderately free of pests.

Transplanting is fairly easy in light but rather difficult in heavy soils. Its woody fruits are somewhat objectionable at times, and a top dieback in some localities has been noted.

THE AMERICAN HOLLY may become a moderate-sized tree 40 feet in height. It has both shade and ornamental value. Its pyramidal crown of glossy evergreen leaves and its brilliant red berries lend beauty throughout the year. Certain individuals and varieties bear fruit much more abundantly than others, so that selections are desirable or necessary. The tree is fairly slow growing, long-lived, and rather resistant to insects and diseases.

Propagation with well-kept transplants is more successful than with wild seedlings. The tree is rather exacting in soil requirements but grows satisfactorily when established in acid soils. Although it is not particularly adaptable, the beauty of the American holly justifies listing it for suitable sites.

THE AMERICAN BEECH is a medium-tall tree, which branches close to the ground and has a large, open-spreading crown. It gives a good, dense shade. Unbroken light-gray bark, maintained throughout its life, is a distinctive characteristic. The tree thrives best on rich, well-drained soils in the mountains or bottom lands and is relatively free of pests.

A number of ornamental varieties of the European beech includes those forms with bronze-purple foliage, weeping branches, and cut leaves. Use of the beech for shade purposes is most common in the Carolinas and more mountainous parts of the region.

THE COMMON CRAPEMYRTLE is extensively planted in the warmer parts of the region. An introduced tree, it is noted for its attractive flower clusters and persistent foliage. It is a small tree with fluted trunk from which the thin bark peels off, leaving a smooth surface. The flowers, 1 to 1.5 inches in diameter, are purple, pink, lavender, or red, and occur in terminal panicles from June to September. The tree is fairly long-lived and slow growing, and is easily cultivated.

It prefers moist conditions during the growing season. In moist soils, it is subject to uprooting by severe storms. It is particularly useful if space is limited and a decorative tree is desired.

THE EASTERN REDBUD is a rather small tree that is extensively favored for ornamental purposes. It usually branches 10 to 15 feet from the ground and forms a narrow erect, or spreading, flattened, or rounded head. Masses of attractive small light-pink to purple flowers appear from late in February to April.

The redbud grows fairly rapidly, is rather free of pests, and is propagated from seed or young transplants. Although moderately hardy, it prefers rich and fairly moist sandy loam soils. Special care in establishing and maintaining the tree may be required in some localities.

THE WATER OAK is a large tree that is grown extensively on wide streets and large lawns. It grows fast in early life and provides quick shade. It is tall and rather slender, with a round-topped, fairly symmetrical crown of ascending branches. Although it is not an evergreen, the leaves often persist until Christmas or after.

It is easily propagated, tolerant of varying conditions, rather short-lived, and somewhat more subject to mistletoe and storm damage than willow oak. Since it provides early shade, is easily handled, and has pleasing symmetry, the water oak is grown widely where adequate space is available.

THE MIMOSA, or silktree albizia, is a rather small tree that is widely cultivated in the Southeast as an ornamental. It grows rapidly under a variety of conditions of soil and has graceful and fernlike leaves and striking colorful flowers. The flowers, pink in color and in clusters at the ends of the branches, usually come in May and June. The seed is produced in large quantities and propagation from seed is easy. A vascular wilt disease has been highly destructive to mimosa, but we hope resistant varieties can be bred.

THE WINGED ELM is medium in size, usually from 40 to 50 feet in height. It develops a short bole, with branches ascending into a fairly open round-topped crown. It is of pleasing proportions and has a somewhat lacy and drooping habit; the branchlets often are corky-winged. The tree grows fairly rapidly. It is moderately long-lived, and does well on dry as well as on rich, moist soils. Propagation from seed or transplants is not difficult. Although relatively resistant to pests, a destructive virus disease is known to attack it. The winged elm lacks some of the graceful qualities of the American elm, but is liked in many places.

THE AMERICAN ELM, a highly prized shade tree, is planted extensively only in the more northern part of this region.