Pinus pinceana (pino piñonero-llorón) description

Pinus pinceana

Gordon 1858

Common names

Pino piñonero-llorón [Spanish]; Pince piñon (Lanner 1981), weeping piñon (Ledig et al. 2001).

Taxonomic notes

Syn: Pinus latisquama Engelmann 1882 (Shaw 1909). Allied to P. maximartinezii and a little less closely to P. rzedowskii. Ledig et al. (2001), using isozymes, found high genetic diversity both within and between the isolated populations of this small species.

Description

A small tree reported to 10 m (Shaw 1909, Perry 1991, Farjon and Styles 1997), though rarely more than 5-6 m tall or 25 cm dbh (M.P. Frankis, field notes, NE Mexico, November 1991). Bark smooth pale grey at first, becoming thinly scaly grey-brown at base on older trees. Crown rounded, dense, with irregular branches and pendulous branchlets. Leaves stiffly drooping, soft bright green, in fascicles of 3, sheath mostly deciduous but smallest basal sheath scales often persisting; 6-12 cm long, about 0.8 mm thick, glossy with inconspicuous stomatal bands. Seedlings have only juvenile foliage for several years, with nodding white shoots and single 3 cm leaves, strongly glaucous. Cones pendulous on slender peduncles 1-3 cm long and 3 mm thick; cylindric, 6-11 cm long, 4-5 cm broad, green ripening bright orange and opening to 5-7 cm broad. Scales large, polygonal, smooth, 20-25 mm broad, apophysis flat to weakly raised, with a flat 7 mm wide umbo. Seeds large, 11-13 mm, orange, wing 1-2 mm, vestigial, usually remaining attached to the scale when seed removed. Seeds do not fall naturally from cone, but are dispersed by birds (Lanner 1981); after seed dispersal the cones fall with or without the peduncle. Cones mature in early November about 18-19 months after pollination (M.P. Frankis, field notes, NE Mexico, November 1991). See García Esteban et al. (2004) for a detailed characterization of the wood anatomy.

Distribution and Ecology

Mexico: Coahuila, N Zacatecas, San Luís Potosí, Querétaro and Hidalgo (Bailey and Hawksworth 1988, Perry 1991), at 1500-2300 m altitude (Perry 1991). See also Thompson et al. (1999). It is scarce and scattered in its natural habitat, in very open scrubland in very dry areas; it usually grows mixed with P. cembroides and mixed xerophytic low scrub vegetation including cacti and agaves (M.P. Frankis, field notes, NE Mexico, November 1991). Hardy to Zone 9 (cold hardiness limit between -6.6°C and -1.1°C) (Bannister and Neuner 2001).

Remarkable Specimens

Ethnobotany

Observations

Perry (1991) gives directions for how to find a stand south of Saltillo. He reports that it occurs scattered in viciously thorny low scrub (Cholla (Opuntia sect. Cylindropuntia), Agave, Ferocactus, etc.) in remote areas with poor roads. Four-wheel drive vehicles, motorcycle or horseback are essential. Also, Nick Macer Cemail 2006.12.31) reports that it can be seen along Mex 120 SW of Pinal del Amoles "where they occur and contrast strikingly with Pinus cembroides, Dasylirion glaucophyllum, and Agave garciae-mendozae." However, I was in this area in 2007.02 and did not succeed in locating the trees.

Remarks

The epithet the epithet honors "Mr. Pince", presumably a nurseryman.

A highly attractive small tree, one of the most beautiful conifers and ideally suited to small gardens in dry areas, but very rare in cultivation.

Citations

Gordon, G. 1858. The Pinetum: being a synopsis of all the coniferous plants at present known... London. (p. 204).

Ledig, F.T., M.A. Capo-Arteaga, P.D. Hodgskiss, H. Sbay, C. Flores-Lopeez, M.T. Conkle, and B. Bermejo-Velazquez. 2001. Genetic diversity and the mating system of a rare Mexican piñon, Pinus pinceana, and a comparison with Pinus maximartinezii (Pinaceae). American Journal of Botany 88: 1977-1987. Available: http://www.amjbot.org/cgi/content/abstract/88/11/1977, accessed 2009.02.06.

This page edited by M.P. Frankis, 1999.01.