Line drawing of several of the varieties; for full size image go to the Flora of China (Wu and Raven 1999).
Good photos are provided by del Tredici (2010).
Line drawing of several of the varieties; for full size image go to the Flora of China (Wu and Raven 1999).
Good photos are provided by del Tredici (2010).
Conservation Status
Tsuga chinensis
铁杉 tieshan [Chinese] (Wu and Raven (1999).
Three varieties:
This species belongs to the Asian clade of Tsuga. It was formerly more widely circumscribed, with some authorities using it to describe all species of Tsuga in Japan and Taiwan except T. dumosa. There have now been detailed molecular studies using nuclear, chloroplast and mitochondrial markers in multiple specimens of all putative taxa, and as a result T. formosana and T. forrestii are now seen as good species, and moreover there is a significant difference between eastern and western provenances of T. chinensis such that the western populations are sister to T. forrestii, with that clade sister to the eastern provenances (Feng et al. 2021). "Western" means Sichuan and Shaanxi and "eastern" means two unspecified locations in eastern China; as a result it is not yet known if there is a sharp discontinuity between the two groups, but since the western populations are located in high mountains on the eastern margin of the Qinghai-Tibetan Plateau and the eastern populations are in relatively low-lying temperate to subtropical mountains, it seems likely that the taxonomic break will be found to reflect topography, and that vars. oblongisquamata and robusta are part of the eastern taxon. The type locality of var. chinensis is in the Daba Shan and further testing will be needed to determine if it represents the eastern or the western taxon.
Trees to 50 m tall and 200 cm DBH, usually with a single trunk, often forked in the crown. Bark rough, scaly, comprised of blackish brown plates, with irregular longitudinal fissures; lenticels inconspicuous; outer bark about 6 mm thick, with alternate tiered layers of pale yellowish brown corky layers and brown lignified fibrous layers; newly formed periderm purplish red; inner bark about 4-5 mm thick, pale reddish brown, fibrous; cambium and newly formed phloem almost inconspicuous. Freshly cut sapwood pale yellowish white, wood rays inconspicuous. Crown broad, becoming irregular or flat-topped with age. Twigs pale yellow-brown, finely grooved between decurrent pulvini; minute pubescence in grooves, soon glabrous. Buds ovoid-globose, 1-4 mm diameter, not resinous, dark or red-brown. Leaves mostly pectinate, 10-20×1.8-3 mm, linear, flattened, grooved above; a midrib separates two stomatal bands below; apex emarginate. Pollen cones crowded near ends of branches, 3-5 mm long, yellow with purple tinge. Seed cones numerous, short-pedunculate, ovoid-oblong when closed, 15-40×10-22 mm, light green ripening light brown. Seed scales nearly circular, 10 mm diameter, lower surface striated. Bracts rhombic with denticulate upper margin, 1-2 mm long. Seeds ovoid-oblong, 3-4×2 mm, light brown, with 6-7×3.5 mm transparent wings (Liu 1970, Farjon 2010). See García Esteban et al. (2004) for a detailed characterization of the wood anatomy.
Var. chinensis differs in that the seed cones are only 15-25×13-22 mm and the cone scale base is short-pedicellate (Farjon 2010). Although Farjon reduces it to synonymy, some authorities distinguish a var. tchekiangensis, which differs in that the twigs are stout (up to 2 mm thick) and reddish-brown rather than pale yellow-brown (Debreczy and Racz 2011).
Var. oblongisquamata differs in that the seed cones are more ellipsoid, 18-28×10-15 mm, and the cone scale base is distinctly petiolate (Farjon 2010).
Var. robusta differs in that the seed cones are up to 40 mm long and the cone scales are proportionally robust and thick (Farjon 2010).
The species as a whole is found in China (incl. Tibet): Anhui, Fujian, S Gansu, Guangdong, Guangxi, N Guizhou, W Henan, W Hubei, Hunan, Jiangxi, S Shaanxi, Sichuan, Xizang, Yunnan, and Zhejiang); and northern Viet Nam. It occurs at elevations of 600 to 3500 m in a wide variety of mixed forests (Wu and Raven 1999, Debreczy and Racz 2011), and dominates a widespread forest altitudinal belt in the mountains of SW China at 2200-2700 m (Liu 1971).
Var. chinensis has the same general range. It occurs on varied soils, in a cool temperate climate with 1000-2000 mm of annual precipitation (Farjon 2010). Authorities who recognize var. tchekiangensis find it at 600-2100 m elevation in SE Yunnan, Guizhou, Hunan, Jiangxi, Zhejiang, N Guangxi, and northern Viet Nam, mainly occurs on karst limestone soils, often in evergreen forest with Amentotaxus yunnanensis, Pinus wangii, and Taxus (Debreczy and Racz 2011).
Var. oblongisquamata has similar ecological tolerances, but is limited to Zhouqu Xian in Gansu, W Hubei, and Sichuan (Farjon 2010).
Var. robusta also has similar ecological tolerances, but is limited to Hubei and the Yalong Valley in Sichuan (Farjon 2010).
T. chinensis is described as hardy to Zone 6 (cold hardiness limit between -23.2°C and -17.8°C) (Bannister and Neuner 2001), though that likely depends upon its provenance.
Trees often attains a diameter of 200 cm, and age often exceeds 400 years (Liu 1971).
This is a valuable timber tree and has been heavily logged in much of its range. The hard, durable wood is used for construction, general carpentry, and shingles. It is rarely seen in ornamental use outside its native range, though it occasionally appears in botanical gardens and large arboreta (Farjon 2010). It has occasionally been used in dendrochronology. There has been limited application in stable carbon isotope studies (Leavitt et al. 1995) and a study of climate variation (Wu 1995), and more recent work has also focused on climate (e.g., Xie et al. 2024).
I have seen it at Hailuogou Glacier Park in Sichuan, where it was common at montane elevations.
The epithet chinensis refers to China.
This species is extraordinarily resistant to hemlock woolly adelgid, an introduced pest that is currently ravaging T. canadensis throughout most of its native range. In an effort to acquire a genetically diverse record and investigate this resistance, collections were made throughout the range of T. chinensis in 1994-1996 and this material was brought to the United States for further study. Growing with native T. canadensis, the species shows comparable growth rates and comparable phenology, with growth both beginning and ending about two weeks earlier in the year, compared to T. canadansis.
Cheng, Wan-Chun, and Li-Kuo Fu. 1975. Gymnospermae Sinicae. Acta Phytotaxonomica Sinica 13(4):68. Available online at the Journal of Systematics and Evolution.
del Tredici, Peter. 2010. Chinese hemlock Tsuga chinensis. Arnoldia 68(2):65-67. Available, accessed 2016.02.14.
Feng, Yuan-Yuan, Ting-Ting Shen, Cheng-Cheng Shao, Hong Du, Jin-Hua Ran, and Xiao-Quan Wang. 2021. Phylotranscriptomics reveals the complex evolutionary and biogeographic history of the genus Tsuga with an east Asian-North American disjunct distribution. Molecular Phylogenetics and Evolution 157:107066. https://doi.org/10.1016/j.ympev.2020.107066.
Franchet, A. R. 1899. Plantarum sinensium ecloge tertia. Journal de Botanique 13(8):259. Available: Biodiversity Heritage Library, accessed 2021.12.18.
Havill, Nathan P., Christopher S. Campbell, Thomas F. Vining, Ben LePage, Randall J. Bayer, and Michael J. Donoghue. 2008. Phylogeny and biogeography of Tsuga (Pinaceae) inferred from nuclear ribosomal ITS and chloroplast DNA sequence data. Systematic Botany 33(3):478–489.
Leavitt, S.W., Malcolm K. Hughes, Liu Y. and An Z. 1995. Stable-carbon isotope tree-ring chronologies from Xian, China. In S. Ohta, T. Fujii, N. Okada, M.K. Hughes and D. Eckstein, eds., Tree Rings: From the Past to the Future. Proceedings of the International Workshop on Asian and Pacific Dendrochronology. Forestry and Forest Products Research Institute Scientific Meeting Report 1:182-186.
Pritzel, G. A. 1900. Gymnospermae, in L. Diels (ed.), Die Flora von Central-China. Bot. Jahrb. Syst. 29(2):211-220. Available: Biodiversity Heritage Library, accessed 2021.12.18.
Wu Xiangding. 1995. Tree-ring width chronologies and their response to climate in the Qinling Mountains, China. In Sheu D.D., R.S. Bradley and Wang W.-C., eds., High Resolution Records of Past Climate from Monsoon Asia: The Last 2000 Years and Beyond. Terrestrial, Atmospheric and Oceanic Sciences 5(3):365-372.
Xie, Mei, Qiufang Cai, Yu Liu, et al. Assessing climatic response and drought resilience in growth of Pinus tabulaeformis Carr. and Tsuga chinensis Pritz. on the southern slope of the Qinling Mountains. Global Ecology and Conservation 53: e02999. https://doi.org/10.1016/j.gecco.2024.e02999.
Luu and Thomas 2004 provide a description, range map, conservation status, drawings and photos, and a wealth of additional information.
Last Modified 2025-02-20
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