Fifty or sixty tropical and temperate-zone species of hackberries include two North American trees which have considerable value for shade and ornamental planting. One hardy Japanese species has been introduced; three exotic species are in cultivation in the South. One is from South Africa, a second from the Mediterranean basin, and a third from the Orient.
It is easy to mistake the hackberry for an elm; the habits of the two trees lead the casual observer astray. The leaf is elm-like, though smaller and brighter green than the foliage of the American elm. A peculiarity of the foliage is the apparent division of the petiole into three main ribs, instead of a single midrib. At base, the leaves are always unsymmetrical. The bark is broken into thick ridges set with warts, separated by deep fissures.
The absence of terminal buds induces a forking habit, which makes the branches of a hackberry tree gnarled and picturesque. The hackberry is not familiarly known by the inhabitants of the regions where it grows, else it would more commonly be transplanted to adorn private grounds and to shade village streets.
The Hackberry
Celtis occidentalis, Linn.
The hackberry reaches one hundred and twenty-five feet in height in moist soil along stream borders or in marshes. It is distributed from Nova Scotia to Puget Sound, and south to Florida, Tennessee, Missouri, Texas, and New Mexico. The beauty of its graceful crown is sometimes marred by a fungus which produces a thick tufting of twigs on the ends of branches. The name, "witches' brooms" has been given to these tufts. Growths of similar appearance and the same name are produced by insect injury on some other trees.
The fruit of the hackberry is an oblong, thin-fleshed sweet berry, purple in color, one fourth to one half inch long. It dries about the solitary seed and hangs on the tree all winter, to the great satisfaction of the birds. (See illustration, [page 183].)
Emerson says: "The wood is used for the shafts and axle-trees of carriages, the naves of wheels, and for musical instruments. The root is used for dyeing yellow, the bark for tanning, and an oil is expressed from the stones of the fruit."
The best use we can make of the hackberry tree is to plant it for shade and ornament. It is easily transplanted, for the roots are shallow and fibrous, so that well-grown trees may be moved in winter time. The autumn yellow of the foliage is wonderfully cheerful, and the warty bark, checked into small thick plates, is interesting at any season.
European Nettle Tree