Common Names

Creeping juniper, savinier, genévrier horizontal (Adams 1993), Bar Harbor juniper in Maine (V. Dinets, e-mail 18-Oct-2003).

Taxonomic notes

Syn: J. communis var. jackii (Silba 1986); Juniperus horizontalis var. douglasii hort.; J. horizontalis var. variegata Beissner. "Juniperus horizontalis, a prostrate species, hybridizes with the trees J. virginiana and J. scopulorum (Adams 1983; Fassett 1945; Palma-Otal et al. 1983) and is closely related to both. The hybrid between J. horizontalis and J. scopulorum has been named J. × fassettii Boivin" (Adams 1993).

Description

"Shrubs dioecious, prostrate to decumbent; crown depressed. Bark brown, exfoliating in thin strips, that of small branchlets (5-10 mm diam.) smooth, that of larger branchlets exfoliating in wide strips or plates. Branches creeping; branchlets erect, 3-4-sided in cross section, ca. 2/3 or less as wide as length of scalelike leaves. Leaves green but turning reddish purple in winter, abaxial gland elliptic, conspicuous, exudate absent, margins entire (at 20× and 40×); whip leaves 4-8 mm, not glaucous adaxially; scalelike leaves 1.5-2 mm, mostly overlapping to 1/3 their length, apex rounded or obtuse to acute and apiculate, spreading. Seed cones mostly maturing in 2 years, of 2 distinct sizes, generally with curved peduncles, globose to ovoid, 5-7 mm, blue-black to brownish blue when mature, lightly glaucous, soft and resinous, with 1-2(-3) seeds. Seeds 4-5 mm. 2n = 22" (Adams 1993).

Range

Canada: all provinces and territories; France: St. Pierre and Miquelon; USA: Alaska, Montana, Wyoming, Nebraska, South Dakota, North Dakota, Minnesota, Iowa, Illinois, Wisconsin, Michigan, New York, Vermont, Massachusetts, New Hampshire and Maine; at 0-1000 m on sand dunes, sandy and gravelly soils, prairies, slopes, rock outcrops, and stream banks (Adams 1993). See also Thompson et al. 1999.

Big Tree

Oldest

Dendrochronology

Ethnobotany

Observations

Remarks

See Also

Farjon (2005) provides a detailed account, with illustrations.