Common juniper, genévrier commun [French] (Adams 1993), Siberian juniper, dwarf juniper, enebro común [Spanish].
Many infraspecific taxa have been described in this highly polymorphic species, but most are sympatric, or merge into each other where they meet. Thus, the observed morphological differences are for the most part explainable on the basis of habitat differences, chiefly climate. This treatment follows Farjon (2005) in recognizing five varieties, but he cautions that further study is needed, and that variation within populations is comparable to the differences described between the varieties. The varieties are as follows:
"Juniperus communis is the most widespread juniper species, and many subspecies and varieties have been described. A major study, including chemical characters, is needed to clarify the taxonomy" (Adams 1993).
"Shrubs or small trees dioecious, to 4 m (if trees, to 10 m), multistemmed, decumbent or rarely upright; crown generally depressed. Bark brown, fibrous, exfoliating in thin strips, that of small branchlets (5-10 mm diam.) smooth, that of larger branchlets exfoliating in strips and plates. Branches spreading or ascending; branchlets erect, terete. Leaves green but sometimes appearing silver when glaucous, spreading, abaxial glands very elongate; adaxial surface with glaucous stomatal band; apex acute to obtuse, mucronate. Seed cones maturing in 2 years, of 2 distinct sizes, with straight peduncles, globose to ovoid, 6-13 mm, bluish black, glaucous, resinous to obscurely woody, with 2-3 seeds. Seeds 4-5 mm. 2n = 22" (Adams 1993).
This is the most widespread conifer in the world, native to temperate Eurasia, and North America N of Mexico, occupying an extraordinary range of habitats (Farjon 2005). Among other places, it is native to Croatia; Sweden; and the United States. See also Thompson et al. 1999. Hardy to Zone 3 (cold hardiness limit between -39.9°C and -34.4°C) (Bannister and Neuner 2001, variety not specified).
"The tallest common juniper in Sweden is 18,5 high and grows at Lake Glypen in the province of Östergötland. The largest ... is found at Råå in the province of Närke. It has a girth of 2,8 m. at breast-height" (Salomonson [no date]).
Ages to 600 years have been reported without supporting data (Salomonson [no date]).
The seed cones are used to flavor gin (Adams 1993).
The only juniper species that occurs in both North America and Eurasia.
Farjon (2005) provides a detailed account, with illustrations and details on the varieties.
Flora Celtica. [no date]. Uses of some common Scottish plants. http://www.rbge.org.uk/data/celtica/Plantuses.htm#Juniperus, accessed 2001.11.28, now defunct.
Last Modified 2014-12-05