1. Juniperus communis Linnaeus, Sp. Pl. 2: 1040. 1753.
Common juniper, genévrier commun
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. 2 n = 22.
Varieties 5 (3 in the flora): North America, Eurasia.
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. J. D. A. Franco (1962) recognized four subspecies (here considered varieties); two of these---var. communis and var. hemisphaerica (J. Presl & C. Presl) Parlatore---do not occur in the flora and a fifth, recognized here, was not treated by Franco.
The seed cones of Juniperus communis are used to flavor gin.