Pinus chiapensis
Pinabete, ocote, pino blanco (Perry 1991).
Section Cembra, the 5-needled white pines. Syn: P. strobus L. var. chiapensis Martínez 1940; P. strobus L. subsp. chiapensis (Martínez) E. Murray 1982. Its close relationship to P. strobus L., of Canada and the eastern U.S., has been substantiated using molecular as well as morphological and chemical evidence. Many authors continue to treat it as a subspecies or variety of P. strobus. The small morphological differences between the two taxa, discussed by Farjon and Styles (1997), can all be accounted for by habitat differences (the taxa are separated by a distance of no less than 2000 km, and by the presence/absence of seasonal frost). It seems likely that we are looking at a classic example of vicariant speciation. However, molecular study of nuclear markers by Syring et al. (2007) reveals that P. strobus and P. monticola are about equally likely as parent species (and indeed P. monticola is so similar to P. strobus that it too could be treated at variety or subspecies rank, though no contemporary authority seriously proposes it). Del Castillo et al. (2009) also propose treatment at species rank, and so it is treated by Threatened Conifers of the World.
Molecular data have also established a close relationship between P. chiapensis and the other Mexican five-needle white pines, P. ayacahuite, P. strobiformis and P. flexilis (Liston et al. 1999, Gernandt et al. 2005, Syring et al. 2007).
Trees to 30-35(-40) m tall and 150 cm dbh. Trunk straight, round, usually single. Branches long, slender, in regular whorls, developing into a pyramidal to open crown. Bark first smooth, green-gray, becoming rough and forming long gray-brown rectangular plates. Branchlets slender, smooth, foliage borne toward the ends. Pulvini not decurrent. Leaves in fascicles of 5, lasting 2-3 years, slender, flexible, somewhat drooping, (5-)8-10(-13) cm long, 0.8-1 mm wide, bright green; margins serrulate under a 10X lens; stomata on the two adaxial surfaces; 2-3 external resin canals; fascicle sheaths light-brown, 10-15 mm long, early deciduous. Pollen cones crowded on the proximal half of new shoots, ovoid-oblong, 5-8 mm long, yellow-green to yellow, subtended by light brown chartaceous bracts. Seed cones subterminal, solitary or in groups of 2-4, purplish and erect in the first year, maturing and pendulous in second year; at maturity borne on 2-3.5 cm long peduncles, brown-yellow, (6-)8-16(-25) cm long, cylindrical when closed, ovoid-oblong when open, fairly straight, often resinous, early deciduous. They mature in August-October, shed their seeds immediately and fall soon after, with the peduncle remaining attached to the cone. Seed scales (40-)50-90(-100), thin, flexible, 10-15 mm wide; apophysis thin, concave, dull brown; umbo terminal without a prickle and usually resinous. Seeds dark brown, 6-7 × 2-4 mm, wing adnate, 20-25 × 4-8 mm. Cotyledons 7-9 (Perry 1991, Farjon and Styles 1997). See García Esteban et al. (2004) for a detailed characterization of the wood anatomy.
Mexico: Chiapas, Guerrero, Oaxaca, Puebla, Veracruz; and Guatemala: El Quiché, Huehuetenango. The northern range limit is near Tlapacoyan in Veracruz, where it grows at 600 m elevation with P. maximinoi and crops such as coffee and bananas. Farther south it grows mostly at higher elevations (500 to 2250 m) but generally makes its best growth on relatively mesic, subtropical to tropical sites with well-drained sandy clay soils. Rainfall is typically 1500-3000 mm/yr, mostly from June to September but in most of its range dense fogs may occur at any time of the year. Thus it is among the most mesic of pines. Common associates include P. maximinoi, P. pseudostrobus, P. pseudostrobus var. apulcensis, P. patula, Podocarpus spp. (I suspect mainly P. matudae), Quercus spp., Liquidamabar styraciflua, Fagus mexicana, Magnolia spp., Platanus mexicana, Ulmus mexicana, Carpinus caroliniana, and Clethra spp. (Perry 1991, Farjon and Styles 1997). Where I have seen it, it grows with trees (especially oaks) that commonly carry a heavy epiphyte load, although P. chiapensis itself seems to bear few epiphytes.
Zone 10 (cold hardiness limit between -1°C and +4.4°C) (Bannister and Neuner 2001).
The wood is soft and creamy, with heartwood only slightly darker. It is locally prized for furniture and finish carpentry (Perry 1991).
Perry (1991) recommends several sites where it can be found, of which the more accessible areas are described here:
(1) On highway Mex-175 from Oaxaca to Tuxtepec, on the steep escarpment where the highway descends from the Continental Divide toward the Gulf of Mexico. This is a spectacularly narrow, steep and winding road; Perry recommends that one person drive while a second looks for the pines. I visited this site and found a small group of particularly large, tall trees very near kilometer 96, about 20 km south (by road) from the town of Valle Nacional.
(2) Along the highway from Teziutlán to Tlapacoyan in Veracruz. This also is described as a very steep, winding, foggy road. HERE is a Google Maps view of the area.
(3) Along highway Mex-195 a few kilometers north of the village of Tapilula in Chiapas.
The epithet chiapensis refers to the type locality, near Ocotopec, Chiapas, where Martínez first collected it in June 1939 (Andresen 1964). Formerly more widespread, the species has been extensively exploited for timber production and is now becoming quite scarce (Perry 1991). Efforts at ex situ conservation and the status of efforts to introduce the species as a timber crop are detailed by Dvorak et al. (2000). I wonder, though, if it was ever very common, at least in historical time. It is odd that the species eluded the very thorough 19th Century botanical exploration of Mexico.
Andresen, J.W. 1964. The taxonomic status of Pinus chiapensis. Phytologia 10: 417-421. Available www.biodiversitylibrary.org/bibliography/12678, accessed 2011.05.16.
del Castillo, R. F., S. T. Argueta, and C. Sáenz-Romero. 2009. Pinus chiapensis, a keystone species: Genetics, ecology, and conservation. Forest Ecology and Management 257(11):2201–2208.
Dvorak, W.S., E.A. Gutiérrez, L.F. Osorio, L. van der Merwe, P. Kikuti, and J.K. Donahue. 2000. Pinus chiapensis. Pp. 34-51 in Conservation & Testing of Tropical & Subtropical Forest Tree Species by the CAMCORE Cooperative. Raleigh, NC: College of Natural Resources, NCSU.
Gernandt, D.S., G. Geada López, S.O. Garcia and A. Liston. 2005. Phylogeny and classification of Pinus. Taxon 54(1):29-42.
Liston, A,, W.A. Robinson, D. Pinero, and E.R. Alvarez-Buylla. 1999. Phylogenetics of Pinus (Pinaceae) Based on Nuclear Ribosomal DNA Internal Transcribed Spacer Region Sequences. Molecular Phylogenetics and Evolution 11(1):95-109.
Syring, J., R. F. del Castillo, R. Cronn, and A. Liston. 2007. Multiple nuclear loci reveal the distinctiveness of the threatened, neotropical Pinus chiapensis. Systematic Botany 32(4):703–717.
The species account at Threatened Conifers of the World.
Dvorak, W.S., J.K. Donahue and J.A. Vásquez. 1996. Provenance and progeny results for the tropical white pine, Pinus chiapensis, at five and eight years of age. New Forests 12: 125-140. Abstract: Eleven provenances and 132 open-pollinated families of Pinus chiapensis were established at six locations in Brazil, Colombia, and South Africa and assessed for height, volume, and forking percent at five and eight years of age. Provenance × site and family × site interactions were examined in a subset of three trials with 38 open-pollinated families in common. Average volume production of P. chiapensis in Colombia and South Africa was 25 m3/ha/yr and 12 m3/ha/yr, respectively, at eight years of age. Provenance and family differences for height and volume were significant at the individual test sites at eight years of age. The La Trinidad (Chiapas) source was the most productive. Forking percent ranged from 3% in South Africa to 38% in San José, Colombia at eight years. Provenance × site interactions were significant for forking but not for height and volume. Family × site interactions were significant for height and volume but not for forking. Forty-six percent of the interaction variance between height and location was contributed by only six families. Height/diameter ratios for P. chiapensis were 0.29 and 0.39 in Colombia and South Africa, respectively, and significantly different.
López-Upton, Javier, and Jeffrey K. Donahue. 2003. Pinus chiapensis. Species description in the Tropical Tree Seed Manual. Available http://www.rngr.net/Publications/ttsm/Folder.2003-07-11.4726 (accessed 2007.08.31).
Wright, J. A., A. M. Marín V. and W. S. Dvorak. 1996. Conservation and use of the Pinus chiapensis resource in Colombia. Forest Ecology and Management 88: 283-288. Abstract: The species Pinus chiapensis is under severe pressure from forest conversion to agriculture an fuelwood cutting. These trends are certain to continue and methods for conservation and wise use of the genetic resource must be implemented soon in Mexico and Guatemala as well as in those countries where the species can be grown on a commercial basis. A total of 101 open-pollinated families from nine provenances of Pinus chiapensis have been established in trials and gene conservation banks by Smurfit Cartón de Colombia since 1981. The best provenances for growth rate have been Cotzal, La Trinidad and Pohlo. A tree improvement program with grafted seed orchards is underway.
Last Modified 2024-11-27