 | Juniperus semiglobosa Regel 1879Common NamesArcha (Russian) (2).Taxonomic notesSyn.: J. talassica Lipsky 1912; J. jarkendensis Komarov 1923; J. shugnanica Komarov 1932; J. excelsa auct., non M.-Bieb; J. macropoda auct., non Boiss (3); J. drobovii, J. tianshanica (1).Description"Habit: tree, occasionally a shrub at tree line, max. height 10-20 m, dbh 1-2 m, usually monopodial, but sometimes multistemmed; branches of first order long, spreading or ascending, in young trees nearly erect; branches of higher orders dense, spreading, from assurgent in young trees to somewhat pendulous in old trees; crown (broad) pyramidal or irregular, open or rather dense; bark of young plants and on branches at first smooth, soon with grey papery flakes, reddish-brown, on old trees fibrous, longitudinally furrowed, peeling off in long strips, reddish-brown to grey-brown. Foliage: branchlets in more or less compact, irregular, often intricate and pendulous sprays; ultimate branchlets numerous but more or less remote, entirely covered with leaves, terete or weakly quadrangular, quite long and thick, 1-2 mm diarn.; older branchlets purplish with grey flakes and leaf remnants. Leaves: juvenile leaves on seedlings and on lower branches of many trees, ternate, acicular, widest at base, pungent, 8-10 x 1 mm, epistomatic; mature leaves predominating on old trees, ternate or decussate, scale-like, imbricate, appressed, incurved at apex, rhombic or triangular, 1-2 mm long on ultimate branchlets, decurrent, (ob)lanceolate-acute and much longer (-9mm) on older shoots, with entire margins; scale leaves amphistomatic, stomata in 2 inconspicuous lines from base to apex; glands large and conspicuous, active, elliptic, often depressed; resin cavity single; colour light green to yellowish-green, lustrous from thick cuticula. Male strobili: numerous on ultimate branchlets, solitary, terminal or subterminal, 3-5 x 2-4 mm, greenish, turning yellowish; microsporophylls 8-10, peltate, with rounded, thin margins, each bearing 3-4 pollen sacs. Female cones: solitary, terminal or subterminal on ultimate branchlets, axillary, sessile; young strobili stellate-spheroid, 2-3mm diam., dark green; mature cones subglobose to triangular, usually irregular and rarely globose, 4-8 mm wide, 4-6 mm high, fleshy, soft or rather hard (in sicco) light brown to blackish-blue, often pruinose; seed scales 4(-6). entirely fused, 3-6 mrn long, the two meeting at the distal pole the largest, smooth, waxy, often wrinkled when dried, with a dorsal, minute umbo being the apex of the fused bract (0.3-0.5 mm); interior of scales resinous, fleshy, yellowish-green. Seeds: ovules 1-2 per fertile scale; seeds (l-)2-3(-4), mostly 2, with apices diverging, angular, broadest at base, more or less ovoid or conical, 3-6 x 2-4.5 mm, yellowish to reddish-brown" (3).RangeHigh mountains of west-central Asia: Kirgizstan, Kazakhstan near Chimkent, Uzbekistan, Tadzikistan, NE Afghanistan (Hindu Kush), Pakistan and India along the Karakoram Range into Kashmir and along the NW Himalaya as far as Garhwal; across the border from Kashmir a single(?) location in the Kunlun Shan of China."Juniperus semiglobosa occurs in the semi-arid high valleys of the great web of mountain ranges in Central Asia, which radiate from the Pamirs in all directions. It reaches ... c.1600 m in the north of its range to 4300 m in the Karakoram Range. To the SE of the Hindu Kush it is rarely found below 2500 m. It is extremely tolerant of drought and heat, but at the same time it must be resistant to frost at any time of the year at the higher altitudes. The cuticula appears to be thicker than in any of the related species and gives the leaves their glossy appearance. In the north it rarely attains a height of more than 8-10 m, but in the Himalaya, e.g. in Lahul, larger trees of 15-20 m are to be found. Near the tree line stunted specimens occur, but it does not attain a prostrate habit like J. excelsa subsp. polycarpos, with which it is in part sympatric. Precipitation is usually less than 400 mm annually, much of it comes as snow. This species is likely to take advantage of snowmelt supplies from alpine and nival zones above it, where a much higher snowfall ensures a more or less constant availability of moisture. It grows on various rocky soils, moraines, stony slopes or even in crevices of bare rock. J. semiglobosa occurs across two Floristic Provinces of the Irano-Turanian Floristic Region (cf. Takhtajan, 1986). In the Turkestanian Province it may form pure stands or mixtures with J. excelsa subsp. polycarpos (especially in NE Afghanistan) and J. turkestania (Pamirs and Tian Shan). In more moist conditions Betula, Populus and Sorbus mix with the Junipers. In the Western Himalayan Province, a monsoon influence is present and it is more often assosiated with other conifers, especially Cedrus deodara, or it forms pure groves. "Browicz & Zielinski (1982) point out that the limits of the range of J. semiglobosa to the north and west are well established, but that the distribution of this species to the south and east 'still require(s) further study', without indicating the reasons for this uncertainty. One of the important conclusions of the present study is, that the arborescent Junipers in the Western Himalaya and Karakoram Range have been generally misidentified, mostly as J. macropoda Boiss., sometimes as J. excelsa M.- Bieb. or J. polycarpos K. Koch (in sched.; Sahni, 1990) and a few times as J. religiosa Carrière, the latter a nom. hort." (3). V. Dinets (2) adds: "This variety and J. pseudosabina var. turkestanica form extensive woodlands or even forests in some areas, from Transcaucasia to Xinjiang. They are logged to extinction for firewood in many areas, but under strict protection in others." Big Tree-Oldest-Dendrochronology-Ethnobotany-Observations-Remarks"In Eurasia, an increased adaptation to continentality can be observed through the taxa J. excela subsp. excelsa, J. foetidissima, J. excelsa subsp. polycarpos and J. semiglobosa. The more equatorial distribution of J. procera ensures a less extreme range of seasonal temperatures, as well as a climate where more moisture is generally available. The distribution of at least two species is also generally connected with major orogenetic events. The East African distribution of J. procera concurs largely with the volcanic uplands adjacent to and associated with the Great Rift systems, along which this species has reached 18°08' S. J. semiglobosa, the most distinct species taxonomically, is a true high altitude species of the mountains in Central Asia. While it crosses a relatively important floristic barrier to the SE, its limit in that direction is nevertheless climatically determined. Increased precipitation levels prevent its eastward expansion, which may be of relatively recent date connected with the rapid uplift of the Karakoram Range (1500 m since the last ice age and still in progress); it is not known from Nepal. For the most part, the geographical ranges found for [these] taxa ... coincide well with the floristic (sub-)regions and provinces as defined by Takhtajan (1986)" (3).Citations(1) Silba 1986.(2) Vladimir Dinets, e-mail communications, 12 Jan 1998. (3) Farjon 1992.
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