Pinus veitchii

Roezl (1857)

Common names

Pino de Navidad [Spanish].

Taxonomic notes

Type: Mexico, Estado de México, near San Rafael Tlalmanalco, on the slopes of the Iztaccíhuatl volcano. Synonymy: see POWO. For most of the time since this species was described in 1857, it was treated as a variety, hybrid, subspecies, or synonym of P. ayacahuite and P. strobiformis. There was little agreement beyond that; morphological analyses showed disagreements, genetic analyses were lacking, and ecological analyses were imprecise; see Ortiz-Martínez et al. (2024) for a review of this history. The puzzle seems to have finally been resolved by an analysis that considered a large number of specimens of all three taxa, 10 different morphological characters, a quantitative estimate of ecological niche divergence, and genetic data in the form of single nucleotide polymorphisms (SNPs). Results indicate that P. veitchii has a narrow distribution, confined to a relatively small part of the Transverse Volcanic Plateau; that it does not have a hybrid origin, but seems to have arisen from P. ayacahuite via allopatric speciation; and that it has been somewhat introgressed by P. strobiformis (alternatively the genetic evidence could be due to incomplete lineage sorting). Moreover, it fits into the overall latitudinal cline (discussed on the P. strobiformis page) from P. flexilis in Alberta to P. ayacahuite in El Salvador (Ortiz-Martínez et al. 2024). The three species are quite morphologically similar and cultivated specimens grown outside their native distribution can easily be misidentified. Species rank is appropriate for P. veitchii, though, because the morphological data show a closer similarity to P. ayacahuite whereas the genetic data show a closer similarity to P. strobiformis; thus it would be misleading to name it as a subspecies or variety of either taxon.

Description

Trees to 30 m tall and 90 cm dbh, slender, straight; crown conic, becoming rounded to irregular. Bark smooth and silvery gray on young trees, aging to a dark grayish brown, furrowed, divided into rough rectangular plates. Branches spreading-ascending; twigs slender, pale red-brown, puberulous or glabrous, sometimes glaucous, aging gray or gray-brown, smooth. Buds ellipsoid, red-brown, ca. 10 mm long, resinous. Leaves 5 per fascicle, spreading to ascending-upcurved, persisting 3-5 years, 4-10 cm × 0.6-1 mm, straight, slightly twisted, pliant, dark green to blue-green, abaxial surface without evident stomatal lines, adaxial surfaces conspicuously whitened by narrow stomatal lines, margins sharp, razorlike and entire to finely serrulate, apex narrowly acute to short-subulate, resin canals 2-4, external; sheath 1.5-2 cm, shed early. Pollen cones cylindric, ca. 6-10 mm, pale yellow-brown. Seed cones maturing in 2 years, shedding seeds and falling soon thereafter, pendent, symmetric, lance-cylindric before opening, broadly lance-cylindric when open, 15-50 cm, creamy brown to light yellow-brown, stalks to 6 cm; apophyses strongly thickened and elongated (reminiscent of P. coulteri) compared to similar species, strongly cross-keeled, tip reflexed; umbo terminal, low. Seeds ovoid; body 10-13 mm, red-brown, with a wing up to twice the length of the seed. 2n=24 (Perry 1991, Farjon and Styles 1997).

Distribution and Ecology

Mexico: Michoacán, Tlaxcala, Estado de México, and Morelos. Perry (1991) would add the Distrito Federal, while Farjon and Styles (1997) add a population in Guanajuato, but regard the Michoacán population as P. strobiformis. Overall, the species has not been collected very often, and seems to have an extremely restricted and fragmented distribution (Ortiz-Martínez et al. 2024). See map on P. strobiformis page showing herbarium records. This tree commonly grows as an emergent in mixed conifer or pine-oak montane forests, often in areas receiving occasional snow, at (2000-)2500-3200(-3600) m elevation.

Distribution data: polygons from USGS (1999), and herbarium records from GBIF (click on points for specific information). Red is P. strobiformis, blue is P. veitchii.

Remarkable Specimens

The largest I have seen was 137 cm dbh and 32 m tall, which we found on the NE slopes of Popocatepetl in 2005. Another tree in the same area was only 105 cm dbh, but 42.1 m tall. I have no other data on big trees.

Ethnobotany

Observations

Remarks

Citations

Roezl, B. 1857. Catalogue des Graines de Coniferes Mexicains, p. 32. Available: Munchener DigitalisierungsZentrum, accessed 2025.02.17.

Ortíz-Martínez, Alfredo, Claudia Patricia Ornelas-García, David Alejandro Moo-Llanes, et al. 2024. Species delimitation using multiple sources of evidence from the Pinus strobiformis-Pinus ayacahuite species complex. Botanical Sciences 102(2):482–498. https://doi.org/10.17129/botsci.3364.

See also

Frankis, Michael P. 2009. The high altitude white pines of Mexico and the adjacent SW USA. International Dendrology Society Yearbook 2008, p. 10.

Leal-Sáenz, Alejandro, Kristen M. Waring, Richard A. Sniezko, et al. 2020. Differences in cone and seed morphology of Pinus strobiformis and Pinus ayacahuite. The Southwestern Naturalist 65(1):9-18. https://doi.org/10.1894/0038-4909-65.1.2.

Musalem, Miguel Angel, and Alvaro Ramírez Luis [compiladores]. 2003. Monografía de Pinus ayacahuite var. veitchii Shaw. Libro Técnico No. 6. División forestal. México, D.F.: Instituto Nacional de Investigaciones Forestales y Pecuarias. 364 p.