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Juniperus Genus

58 Species with 405 Trinomials

Junipers are coniferous plants in the genus Juniperus of the cypress family Cupressaceae. Depending on taxonomic viewpoint, there are between 50-67 species of juniper, widely distributed throughout the northern hemisphere, from the Arctic, south to tropical Africa in the Old World, and to the mountains of Central America.

Junipers vary in size and shape from tall trees, 65 – 130′ (20–40 m) tall, to columnar or low spreading shrubs with long trailing branches. They are evergreen with needle-like and/or scale-like leaves. They can be either monoecious or dioecious. The female seed cones are very distinctive, with fleshy, fruit-like coalescing scales which fuse together to form a “berry”-like structure, 4–27 mm long, with 1-12 unwinged, hard-shelled seeds. In some species these “berries” are red-brown or orange but in most they are blue; they are often aromatic and can be used as a spice. The seed maturation time varies between species from 6–18 months after pollination. The male cones are similar to those of other Cupressaceae, with 6-20 scales; most shed their pollen in early spring, but some species pollinate in the autumn.

Many junipers (e.g. Juniperus chinensis, Juniperus virginiana) have two types of leaves: seedlings and some twigs of older trees have needle-like leaves 5–25 mm long; and the leaves on mature plants are (mostly) tiny (2–4 mm long), overlapping and scale-like. When juvenile foliage occurs on mature plants, it is most often found on shaded shoots, with adult foliage in full sunlight. Leaves on fast-growing ‘whip’ shoots are often intermediate between juvenile and adult.

Juniperus osteosperma in Canyonlands National Park in Utah
Juniperus osteosperma in Canyonlands National Park in Utah

Photo by Flicka via Wikipedia

In some species (e. g. Juniperus communis, Juniperus squamata), all the foliage is of the juvenile needle-like type, with no scale leaves. In some of these (e.g. Juniperus communis), the needles are jointed at the base, in others (e.g. Juniperus squamata), the needles merge smoothly with the stem, not jointed.

The needle-leaves of junipers are hard and sharp, making the juvenile foliage very prickly to handle. This can be a valuable identification feature in seedlings, as the otherwise very similar juvenile foliage of cypresses (Cupressus, Chamaecyparis) and other related genera is soft and not prickly.

Juniper is the exclusive food plant of the larvae of some Lepidoptera species including Bucculatrix inusitata and Juniper Carpet, and is also eaten by the larvae of other Lepidoptera species such as Chionodes electella, Chionodes viduella, Juniper Pug and Pine Beauty; those of the Tortrix Moth Chionodes duplicana feed on the bark around injuries or canker.

The number of juniper species is in dispute, with two recent studies giving very different totals, Farjon (2001) accepting 52 species, and Adams (2004) accepting 67 species. The junipers are divided into several sections, though (particularly among the scale-leaved species) which species belong to which sections is still far from clear, with research still on-going. The section Juniperus is an obvious monophyletic group though.

Juniper berries are a spice used in a wide variety of culinary dishes and best known for the primary flavoring in gin (and responsible for gin’s name, which is a shortening of the Dutch word for juniper, genever). Juniper berries are also used as the primary flavor in the liquor Jenever and sahti-style of beers. Juniper berry sauce is often a popular flavoring choice for quail, pheasant, veal, rabbit, venison and other meat dishes.

Many of the earliest prehistoric people lived in or near juniper forests which furnished them food, fuel, and wood for shelter or utensils. Many species, such as Juniperus chinensis (Chinese Juniper) from eastern Asia, are extensively used in landscaping and horticulture, and as one of the most popular species for use in bonsai. It is also a symbol of longevity, strength, athleticism, and fertility.

Some junipers are susceptible to Gymnosporangium rust disease, and can be a serious problem for those people growing apple trees, the alternate host of the disease.

Some junipers are given the common name “cedar,” including Juniperus virginiana, the “red cedar” that is used widely in cedar drawers.

In Morocco, the tar (gitran) of the arar tree (Juniperus phoenicea) is applied in dotted patterns on bisque drinking cups. Gitran makes the water more fragrant and is said to be good for the teeth.

American Indians, such as the Navajo, have traditionally used juniper to treat diabetes. Animal studies have shown that treatment with juniper may retard the development of streptozotocin-induced diabetes in mice. Native Americans also used juniper berries as a female contraceptive. The 17th Century herbalist physician Nicholas Culpeper recommended the ripened berries for conditions such as asthma and sciatica, as well as to speed childbirth.

Juniper berries are steam distilled to produce an essential oil that may vary from colorless to yellow or pale green. Some of its chemical components are alpha pinene, cadinene, camphene and terpineol.

Juniper in weave is a traditional cladding technique used in Northern Europe, e.g. at Havrå, Norway.

Attributed from: Wikipedia

Miscellaneous Hybrid Junipers

(Juniperus ×)

Juniperus angosturana

 

Ashe juniper

(Juniperus ashei)

West Indies juniper

(Juniperus barbadensis)

Bermuda cedar

(Juniperus bermudiana)

Juniperus blancoi

 

Azores juniper

(Juniperus brevifolia)

California juniper

(Juniperus californica)

Canary Islands juniper

(Juniperus cedrus)

Chinese juniper

(Juniperus chinensis)

Juniperus coahuilensis

 

Juniperus comitana

 

Common juniper

(Juniperus communis)

Shore juniper

(Juniperus conferta)

Juniperus convallium

 

Dahurian juniper

(Juniperus davurica)

Alligator juniper

(Juniperus deppeana)

Syrian juniper

(Juniperus drupacea)

Juniperus durangensis

 

Greek juniper

(Juniperus excelsa)

Weeping juniper

(Juniperus flaccida)

Foetid juniper

(Juniperus foetidissima)

Formisan juniper

(Juniperus formosana)

Juniperus gamboana

 

Juniperus gaussenii

 

Juniperus gracilior

 

Creeping juniper

(Juniperus horizontalis)

Black juniper

(Juniperus indica)

Juniperus jaliscana

 

Juniperus komarovii

 

One-seed juniper

(Juniperus monosperma)

Juniperus monticola

 

Western juniper

(Juniperus occidentalis)

Utah juniper

(Juniperus osteosperma)

Juniperus oxycedrus

 

Phoenicean juniper

(Juniperus phoenicea)

Pinchot juniper

(Juniperus pinchotii)

Ping's juniper

(Juniperus pingii)

African juniper

(Juniperus procera)

Japanese garden juniper

(Juniperus procumbens)

Przewalski's juniper

(Juniperus przewalskii)

Turkestan juniper

(Juniperus pseudosabina)

Drooping juniper

(Juniperus recurva)

Temple juniper

(Juniperus rigida)

Savin juniper

(Juniperus sabina)

Juniperus saltillensis

 

Juniperus saltuaria

 

Juniperus saxicola

 

Rocky Mountain juniper

(Juniperus scopulorum)

Himalayan Pencil juniper

(Juniperus semiglobosa)

Flaky juniper

(Juniperus squamata)

Juniperus standleyi

 

Bonin Islands juniper

(Juniperus taxifolia)

Spanish juniper

(Juniperus thurifera)

Tibetan juniper

(Juniperus tibetica)

Eastern Red-cedar

(Juniperus virginiana)

Juniperus x media

 

Juniperus x pfitzeriana

 

Juniperus_squamata