Trees & Shrubs – The Juniper – Juniperus communis, the common juniper
Junipers are coniferous plants in the genus Juniperus /dʒuːˈnɪpərəs/ of the cypress family Cupressaceae in division Pinophyta, also known as division Coniferophyta or Coniferae.
Depending on taxonomic viewpoint, between 50 and 67 species of juniper are widely distributed throughout the Northern Hemisphere.
Listed as a native species by The RHS. Juniperus communis or Common juniper: 6m, grows in any well-drained soil. One of three conifers (Coniferae) native to the UK alongside The Scots Pine (Pinus sylvestris) and The Yew (Taxus baccata).
Juniperus communis, the common juniper, is a species in the genus Juniperus, in the family Cupressaceae. It has the largest range of any woody plant, throughout the cool temperate Northern Hemisphere from the Arctic south in mountains to around 30°N latitude in North America, Europe and Asia.
The Juniper (Juniperus communis)
Fruits of Juniper.
Juniper in fruit. A, flowers.
The Juniper (Juniperus communis) is seldom more than a shrub a few feet in height, though it occasionally develops into a small tree from ten to twenty feet high, and with a girth of five feet. It has a fibrous red bark, which flakes off like that of the Yew. The leaves are shaped like a cobbler’s awl, rigid, and end in sharp points. They have thickened margins, the concave upper sides are glaucous, and they are arranged round the branches in whorls of three. The male and female flowers are on separate trees. The male catkin may be known in May by its numerous anthers and pale yellow pollen. The female catkins will be found in the axils of the leaves, and resemble buds. The scales are fleshy, and after fertilization the upper ones slowly develop into the form of a berry, which has a few undeveloped scales at its base. They do not ripen until the following year, when they are blue-black, covered with a fine glaucous bloom. They have a pungent flavour, which is utilized in concocting gin, which indeed owes its name to this fact—the word being merely a contraction of genévrier, the French form of Juniper. The “berries” have long been known as a kidney stimulant—a fact which has been fully utilized as the justification of every gin-drinker. A beautiful little moth—Hypsilophus marginellus—may often be taken about the Juniper, upon which its caterpillar feeds.
To appreciate the variety of forms assumed by the Juniper according to the elevation at which it grows, it should be seen on slopes like those of the North Downs in Surrey—one portion of the range at Mickleham is named Juniper Hill. In the valleys it may be found as a small shapely tree, higher up the slopes as a pyramidal shrub, and as we reach higher and more exposed positions, the Juniper gradually dwindles to a low, shapeless bush. This, however, must not be confounded with a distinct variety to which the name nana has been applied; it differs from the type in having shorter and broader overlapping leaves, with curved tips. Var. nana is confined to the mountains of the north of our islands, and ascends to 2700 feet, which is 300 feet higher than is recorded of the type.
The Virginian Juniper (Juniperus virginiana), or “Red Cedar,” as it is called on the American continent, is a much larger plant, which is frequently planted in our parks and gardens. It varies in habit, and may be low and spreading, bush-like, or tall and tapering, thirty to forty feet high. Its leaves are in threes, like those of our native species, but the three are united by their bases. It is with the red heart-wood of this tree that our “cedar” pencils are covered, large quantities of the timber of J. virginiana, and formerly of J. bermudiana, being imported for the purpose. The Virginian Juniper has been with us for many years. It is mentioned by Evelyn in his “Sylva” (1664), and is believed to have been introduced by him from North America.