JUNIPER, a genus (Juniperus) of ornamental evergreen trees and shrubs of the family Juniperaceæ, consisting of about 40 species, distributed mainly throughout the cooler parts of the northern hemisphere. The species have branches which spread in all directions from the main trunk and limbs, small, rigid, needle-like or scale-like, opposite leaves; unisexual flowers, the two sexes usually upon separate plants, the staminate yellow and in catkins, the greenish pistillate ones followed by fleshy or dry, berry-like cones containing from one to six, sometimes 12 seeds, which may not attain maturity until the second or third year. The best-known species in the United States is probably the Virginia juniper, red cedar or savin (Juniperus virginiana), to be found widely dispersed east of the Rocky Mountains, upon rocky and sandy soils, mountain sides, etc. It sometimes attains 100 feet in height, its upright or spreading branches forming a handsome conical head. Its numerous attractive horticultural varieties are largely planted in parks and cemeteries. The trunks are highly prized for fence posts, being exceedingly durable; the handsome red heartwood is valued for turning, cabinet-work, cooperage and especially for lead pencils; but the tree is looked upon with disfavor by the orchardist, because it is one of the hosts of apple rust. See Apple, paragraph Diseases.
The common juniper (J. communis) is a smaller species, rarely reaching 50 feet in height and usually less than 25 feet tall, and many of its numerous varieties less than 10 feet. It is widely distributed throughout the northern hemisphere, especially in the colder latitudes and altitudes. Like the preceding species its wood is valued, when of sufficient size, for posts, veneers, pencils and for turning. The tree itself is also used for ornamental planting. Its bark is sometimes twisted into ropes and its long, tough, fibrous roots are used for making baskets. Its blue-black fruit, which it yields profusely, is used for flavoring certain liquors, as is also the oil obtained from them and from the twigs by distillation with water. This oil has been used in medicine as a stimulant, but is less popular than formerly. The Bermuda cedar (J. barbadensis) resembles the Virginia juniper, but is of stouter build, though it rarely exceeds 40 feet in height. Its wood is rather more fragrant than that of the preceding species like which it is used. Formerly it was employed in the ships built in the Bermudas, but the forests which supplied this industry were mismanaged and the industry perished. Several other species are of more or less economic importance; for instance, the Spanish juniper (J. oxycedrus) , a shrub which attains a height of about 12 feet, whose fruits yield a disagreeable smelling oil (oil of cade), used in veterinary medicine; and African juniper (J. procera), a useful timber species and probably the largest of the genus, often attaining heights of 150 feet m the mountains of eastern Africa, where it is native. A number of species occurring in western North America are of great economic importance.
Junipers succeed best in moderately moist, sandy loam in open, sunny situations. They make excellent windbreaks and shelter belts, especially where the soil is too dry, rocky, or gravelly for other trees. They may be propagated by seeds which, however, usually require two, sometimes three, years to germinate. Cuttings of almost mature wood may be taken in the autumn from the needle-leaved kinds and grown under glass or in the open; species with scale-like leaves are generally side-grafted in the greenhouse during winter. Some of the shrubby species are propagated by layers.