Pinus henryi (巴山松 Henry's pine) description

Pinus henryi

Mast. 1890

Common names

巴山松 ba shan song [Chinese], Thông đá vôi quả nhó [Vietnamese], Henry's pine.

Taxonomic notes

Synonymy:

Pinus massoniana Lamb. var. henryi (Mast.) C.L. Wu 1956;
Pinus tabuliformis Carr. var. henryi (Mast.) C.T. Kuan 1983;
Pinus massoniana Lamb. var. wulingensis C.J. Qi & Q.Z. Lin 1988;
Pinus tabuliformis Carr. subsp. henryi (Mast.) Businský 1999;
Pinus hwangshanensis auct. non W.Y. Hsia: Phan et al., Ecol. Econ. J. (Viet Nam) 45: 43, 2013b.

Type: Hubei, Fang, A. Henry 6909. This species has generally been treated as either a good species or a variety of P. tabuliformis, though Loc et al. (2017) also note a close relationship to P. hwangshanensis. Liu et al. (2012a, b) present molecular evidence that P. henryi and P. tabuliformis are clearly distinct species, and that P. henryi and P. hwangshanensis may be sister species. Molecular analysis has consistently placed P. henryi in a clade with other Asian pines in subsection Pinus, viz. P. densata, P. hwangshanensis, P. kesiya, P. luchuensis, P. thunbergii, P. tabuliformis and P. yunnanensis (Geada Lopez et al. 2002, Gernandt et al. 2005).

Description

Monoecious evergreen trees to 30 m tall and 100 cm dbh, typically with a single straight trunk and spreading or downcurving branches forming a flat-topped crown. Bark on mature trees scaly, fissured, breaking into large irregular plates, gray-brown, flaky. Twigs thick, rough with pulvini after shedding leaves, glabrous, new shoots red-brown, usually glaucous, turning light brown to gray. Buds oblong, acute, up to 20 mm long, slightly resinous; scale leaves appressed, pale brown. Leaves in fascicles of 2, persisting 2-3 years, spreading, held in a 10-15 mm long persistent basal sheath, 7-12 cm long, straight or curved, pliant, 0.7-1 mm thick, often slightly twisted, green; apex acute or acuminate; stomata in fine lines on all surfaces. Pollen cones in clusters at base of new shoots, spirally arranged, short cylindrical, ca. 2 cm long, yellow. Seed cones solitary or in pairs, short pedunculate, usually persisting a few years but opening soon, ovoid when closed, nearly symmetrical, 2.5-5 × 2.5-5 cm when open. Seed scales thin woody, stiff, obovate, often recurving, brown. Apophyses slighty raised, transversely keeled or with 4 radial ridges, bearing a short (less than 1 mm) and stout spine; ripening from green to lustrous brown or reddish brown. Seeds ovoid-oblong, 3.5-5 × 2-3 mm, pale brown, often mottled; wing 9-12 × 4-5 mm, dark brown. Pollination March–April; seed maturity about 16–18 months later, August–October in following year (Farjon 2010, Loc et al. 2017).

Distribution and Ecology

China: Chongqing, Hubei, Hunan, Shaanxi, Sichuan; Viet Nam: Ha Giang and Bac Kan. Farjon (2010, 2013) limits this species to China, while Loc et al. (2017) additionally place it in far northern Viet Nam, citing sources from as early as 2007 (as P. tabuliformis var. henryi). Although the conservation status is "near threatened" based on the species' broad extent in China (Farjon 2013), it is regarded as "endangered" in Viet Nam where it is quite rare and protected in only one location, the Na Hang nature reserve (Loc et al 2017). The Chinese populations are declining due to threats that include ongoing declines due to deforestation and timber harvest (Farjon 2013).

In China, P. henryi occurs in subtropical mountainous areas at elevations of 1100-2000 m, primarily on dry, sunny slopes where competition from broad-leaved trees is less severe. It is also an early-successional species, commonly mixed with deciduous shrubs and trees that later acquire dominance and exclude it (Farjon 2010). In Viet Nam, it is confined to limestone mountains in primary closed evergreen seasonal tropical conifer forests at elevations of 900–1500 m (Loc et al. 2017).

Remarkable Specimens

Ethnobotany

The wood is of good quality for construction and furniture, similar to that of P. tabuliformis, but as this species is much less common and widespread, its social and economic importance are less (Farjon 2013, Loc et al. 2017). It is rarely seen outside of habitat, being found only in major botanical gardens and arboreta.

Observations

Remarks

The epithet remembers Augustine Henry (1857-1930), the English plantsman who collected the type specimen. Henry spent much of the 1880s and 1890 collecting in China, and who is remembered in the names of many Chinese plants.

Citations

Farjon, Aljos. 2010. A Handbook of the World's Conifers. Leiden, Netherlands: Brill Academic Publishers.

Farjon, A. 2013. Pinus henryi. The IUCN Red List of Threatened Species 2013: e.T37555A2866837. https://dx.doi.org/10.2305/IUCN.UK.2013-1.RLTS.T37555A2866837.en. Downloaded on 19 May 2020.

Geada López, G., K. Kamiya, and K. Harada. 2002. Phylogenetic relationships of diploxylon pines (Subgenus Pinus) based on plastid sequence data. International Journal of Plant Sciences 163(5):737–747.

Gernandt, D. S., G. Geada López, S. O. García, and A. Liston. 2005. Phylogeny and Classification of Pinus. Taxon 54(1):29.

Liu, Z.L., Cheng, C. and Li, J. 2012a. High genetic differentiation in natural populations of Pinus henryi and Pinus tabuliformis as revealed by nuclear microsatellites. Biochemical systematics and ecology 42:1-9.

Liu, Z.L., Yang, X., Zhang, H., Zhang, J. and Li, J.F. 2012b. Systematic position of Pinus henryi (Pinaceae) as revealed by multiple evidence. Nordic journal of botany 30(6):671-679.

Loc, P. K., P. V. Te, P. K. Long, J. Regalado, and L. V. Averyanov. 2017. Native conifers of Vietnam – a review. Pakistan Journal of Botany 49(5):2037–2068.

Masters, M.T. 1890. Coniferae. J. Linn. Soc., Bot. 26:550. Available: Biodiversity Heritage Library, accessed 2020.05.19.