Juniperus ashei

Buchholz 1930

Common names

Ashe juniper, mountain cedar (Adams 1993), post cedar, rock cedar, Ozark white cedar, Mexican juniper (Farjon 2005).

Taxonomic notes

Synonymy (Farjon 2005):

• Juniperus occidentalis Hook. var. texana Vasey 1875
• Juniperus occidentalis Hook. var. conjugens Engelm. 1878
• Juniperus sabinoides Sarg. 1896, non Griseb. (1846), excl. syn. Cupressus sabinoides Kunth.
• Sabina sabinoides Small 1903 excl. ref. ("HBK") to syn. Cupressus sabinoides Kunth.

Type locality Sylamore, Arkansas (Farjon 2005).

Adams (1993) says that "reports of hybridization with J. virginiana and J. pinchotii have been refuted using numerous chemical and morphologic characters." Farjon (2005) expresses some doubt about this, and adds his opinion that J. ashei is "very similar to J. monosperma, and seems to be an eastern vicariant of it," asserting that these are two members of a "species complex" that includes J. ashei, J. pinchotii, J. monosperma, J. angosturana, and J. coahuilensis.

Description

Dioecious large shrub or small tree, 6-10(-15) m tall, usually single-stemmed for basal 1-3 m, up to 50 cm dbh. Branches long, spreading to ascending, forming an open to dense, irregular to rounded crown. Bark on small branches first pink turning gray and flaking; on trunk and large branches brown, weathering gray and exfoliating in thin strips. Foliage branches numerous, irregular, not pendulous. Ultimate branchlets spreading to erect, stiff, 5-10(-20) × 0.9-1.3 mm, 4-sided in cross section (whip shoots occasionally 3-sided), covered with closely appressed leaves, persistent. Leaves on lateral branchlets variably green, scale-like, decurrent, (slightly) imbricate, rhombic, often keeled, acute, with finely denticulate margins, 1-2 × 0.8-1.2 mm, with stomata on the abaxial side limited to decurrent leaf base, on the adaxial surface in two bands; glands obscure, hemispheric, raised, terminating a single resin cavity, without exudate. Pollen cones numerous, terminal, solitary, subglobose to ovoid, 2-4 x 2 mm, yellow-green maturing to pink or light brown. Seed cones maturing in 1 year, terminal on straight short branchlets, young cones pink glaucous, maturing dark blue, globose to broadly ovoid, 6-9 mm, succulent and resinous, with 1-2(-3) seeds. Seeds broad ovoid, 4-6 x 3-4.5 mm, not flattened, lustrous yellow-brown to chestnut brown, with a lighter hilum. Cotyledons 2, juvenile leaves restricted to seedlings, decurrent, the free part 7-10 x 0.8-1.3 mm. 2n = 22 (Adams 1993, Farjon 2005).

Similar species: J. monosperma usually has only one seed per cone, and unlike J. ashei, does not coppice (Farjon 2005).

Range

Mexico: Coahuila; USA: Arkansas, Missouri (Ozark Mts.), Oklahoma, Texas (Edwards Plateau); at (150-)600-1550 m elevation on limestone glades and bluffs, or along streambeds. Grows sometimes with Juniperus pinchotii, Pinus remota, Quercus spp. Climate continental, with warm summers and cold winters (Adams 1993, Farjon 2005). See also Thompson et al. 1999.

Big tree

Diameter 93 cm, height 12 m, crown spread 11 m, located in Comal County, TX (American Forests 1996).

Oldest

Dendrochronology

Ethnobotany

Observations

Remarks

Citations

See also