Juniperus formosana
Formosan juniper, prickly cypress (Vidakovic 1991).
Type: Taiwan, Nantou, Chia-i Pref., Yushan ("Mt. Morrison"), T. Kawakami & U. Mori 2039 (lectotype TI). Synonymy:
This species belongs to Juniperus section Juniperus, where it is sister to the species of the J. communis complex (Adams and Schwarzbach 2012).
I here recognize one variety, J. formosana var. mairei (Lemée & Lev.) R.P. Adams et C.F. Hsieh (Adams et al. 2002) (syn. J. mairei Lemée et Lev. 1914, J. formosana subsp. mairei (Lemée & H.Lév.) Silba in 2006). Farjon (2005) reduced the variety to synonymy, but other authorities (e.g. Adams 2014) treat it as a good species. Evidence for species rank includes range disjunction (the variety found in China, with J. formosana s.s. endemic to Taiwan) and molecular taxonomy (Adams and Schwarzbach 2012). The molecular data include nrDNA and cpDNA differences that place J. formosana sister to mairei, also close to J. jackii of North America. The differences are small and the analysis was based on a single specimen from each taxon; level of confidence is low, and there have been no independent studies to confirm or deny the relationship. Also, morphological differences are small at best and no ecological or habitat differences seem to have been documented. Biogeographically, var. mairei is widespread in China while var. formosana is a relatively restricted Taiwan endemic, so it is quite possible that var. mairei is the older taxon with var. formosana having reached Taiwan via migration over the Tungshan Land Bridge, which connects China and Taiwan when sea level is at least 80 m lower than at present (Huang 2014). Pending further information, there is no apparent reason to treat var. mairei at species rank.
Dioecious shrubs, or trees to 25 m tall, often multi-stemmed or low-branching, with a pyramidal crown of spreading or ascending branches; crown often very dense and irregular at high elevations. Leaves in whorls of 3, spreading at nodes 3-10 mm apart, stiff, linear-lanceolate, (4-)10-20(-30) × 1-2.1 mm, broadest near the middle, abaxial surface weakly keeled, margins entire, apex acuminate or pungent, epistomatic with stomata in two conspicuous whitish bands flanking a midrib, with green margins about as wide as the midrib. Pollen cones axillary, solitary, 1-2 per leaf whorl, subglobose to ovoid, 4-6 × 3-4 mm. Seed cones axillary on 1-2 mm dwarf shoots, maturing in 1 year, at maturity subglobose, 6-9 mm diameter, dry pulpy, slightly pruinose. Seed 2-3 per cone, 4-5 × 3-3.5 mm, light brown with an obtuse apex (Farjon 2010). See García Esteban et al. (2004) for a detailed characterization of the wood anatomy.
Adams (2014) differentiates var. formosana from var. mairei as having leaves with a "raised, elongate to linear gland" vs. a "raised, oval to elliptical gland." Also, var. formosana seed cones are reddish-brown, turning black on maturity; the cones of var. mairei are glaucous green, turning reddish on maturity.
Var. formosana in Taiwan: (1900-)2500-3830 m elevation in Yushania forest, mixed conifer-broadleeaf forest, and above treeline. 120°44'41"E to 121°38'21"E, by 22°36'41"N to 24°28'03"N. Includes Sheipa, Taroko and Yushan National Parks (HAST 1999). Var. mairei in China: S Anhui, Chongqing, W Fujian, E Gansu, Guizhou, W Hubei, S Hunan, S Jiangsu, Jiangxi, NE Qinghai, S Shaanxi, Sichuan, S Xizang (Tibet), Yunnan, Zhejiang. Found on varied soil types in mixed conifer forest, secondary conifer woodland, grassland, and at high altitudes on grassy/shrubby slopes (Farjon 2010). Presence of var. formosana in China, near Taiwan, is possible, not confirmed. Hardy to Zone 8 (cold hardiness limit between -12.1°C and -6.7°C) (Bannister and Neuner 2001).
The IUCN assesses this species as of "Least Concern" for conservation due to its very wide distribution. The conservation status of the varieties does not appear to have been separately assessed, but as var. formosana primarily occurs at high elevations in protected areas, it is probably also of low concern despite its relatively restricted range.
No data as of 2023.03.03.
Farjon (2010), probably in reference to var. mairei, describes it as a popular ornamental in east Asia, usually appearing as a columnar cultivar.
Shei-Pa, Taroko and Yushan National Parks look like good places to see var. formosana.
The epithet arose because early Portuguese traders and explorers gave Taiwan the European name "Isla Formosa", meaning "beautiful island". The name "Formosa" was commonly applied to the island well into the 20th century, and many of its organisms bear the epithets formosana or formosensis.
This is one of over a dozen east Asian conifers described to science by prolific Japanese botanist Bunzo Hayata (1874-1934), who was first to publish the names of about 1600 Taiwanese plants (Ohashi 2009).
Adams, Robert P. 2014. Junipers of the World: The Genus Juniperus. Fourth edition. Trafford Publishing. Brief versions of the descriptions are available online at Adam's website, www.juniperus.org.
Adams, Robert P., Chang-Fu Hsieh, Jin Murata, and Ram Naresh Pandey. 2002. Systematics of Juniperus from eastern Asia based on Random Amplified Polymorphic DNAs (RAPDs). Biochemical Systematics and Ecology 30(3):231–41.
Adams, Robert P. and Andrea E. Schwarzbach. 2012. Taxonomy of Juniperus section Juniperus: sequence analysis of nrDNA and five cpDNA regions. Phytologia 94:269-276.
Hayata, Bunzo. 1908. J. Coll. Sci. Imp. Univ. Tokyo 25(19):209. Available: Biodiversity Heritage Library, accessed 2025.01.08.
Herbarium of the Research Center For Biodiversity, Academia Sinica, Taipei [HAST]. 1999. Database output at http://www2.sinica.edu.tw:8080/hast/eindex.html, accessed 1999.03.15, now defunct.
Huang Shing-Fan. 2014. Hypothesizing origin, migration routes and distribution patterns of gymnosperms in Taiwan. Taiwania 59(2):139–63. https://doi.org/10.6165/tai.2014.59.139.
Ohashi, Hiroyoshi. 2009. Bunzo Hayata and His Contributions to the Flora of Taiwan. Taiwania 54(1):1-27.
TROPICOS - Flora of China Checklist, formerly at http://mobot.mobot.org/cgi-bin/search_pick, accessed 1998.11.02, now defunct.
Elwes and Henry 1906-1913 at the Biodiversity Heritage Library. This series of volumes, privately printed, provides some of the most engaging descriptions of conifers ever published. Although they only treat species cultivated in the U.K. and Ireland, and the taxonomy is a bit dated, still these accounts are thorough, treating such topics as species description, range, varieties, exceptionally old or tall specimens, remarkable trees, and cultivation. Despite being over a century old, they are generally accurate, and are illustrated with some remarkable photographs and lithographs.
Farjon (2005) provides a detailed account, with illustrations.
Huang 1994 (the Flora of Taiwan).
Last Modified 2025-01-08
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