Pinus lambertiana Douglas
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Authority
Farjon, Aljos K. & Styles, Brian T. 1997. Pinus (Pinaceae). Fl. Neotrop. Monogr. 75: 1-291. (Published by NYBG Press)
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Family
Pinaceae
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Scientific Name
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Type
Type. United States. Oregon: Aug 1825 (or Oct 1826), Douglas s.n. (lectotype, K, 2 foliage specimens numbered (1) and with Douglas s remark: Gum from a Larch tree, eaten by the natives, Douglas, here designated).
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Synonyms
Pinus lambertiana var. martirensis Silba
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Description
Species Description - Tree, medium to tall, height to 30-40 m, dbh to 80-120 cm. Trunk straight, terete, the bole often free of branches ½ or more of its length. Bark thick, rough, scaly, on the lower part of the trunk breaking into increasingly large, irregular to longitudinal plates separated by deep fissures, cinnamon- to grey-brown, on young trees and branches thin, smooth, greyish green, turning brown. Branches of first order often widely spaced, long, spreading horizontally, curved downward toward the ends; branches of higher orders numerous, considerably shorter than the main branches, spreading or drooping, the ultimate branches assurgent. The crown is broadly conical, lobed, in old trees often flat-topped from windbreak. Shoots slender, flexible, puberulent at first but soon glabrous, rough with small pulvini, orange-brown turning light grey. Cataphylls small, triangular, scarious, with thin, hyaline margins, soon deciduous. Vegetative buds ovoid-oblong, the terminal buds 5-10 X 4-6 mm, the laterals smaller, not resinous; the scales triangular, orange-brown with hyaline margins. Fascicle sheaths 10-15 mm long on young fascicles, with 5-8 thin, loosely imbricate, orange-brown scales, soon deciduous and absent when the leaves are full-grown. Leaves in fascicles of 5, in small, dense tufts toward the ends of branches, persisting 2-4 years, straight, slightly twisted, lax, spreading at ca. 45° from the shoot, (3.5-)4-8(-10) cm X 0.8-1.5 mm, with remotely and sometimes scarcely serrulate margins, apex acute-acuminate, green to glaucous-green. Stomata on all faces of leaves, in 2-4(-5) intermittent lines on the abaxial face and 3-4 lines on each adaxial face. Leaf anatomy: Cross section triangular, with equal sides; hypodermis unilayered or near the margins with 2-3 layers of cells; resin ducts 2-3, external, rarely 1 internal; stele terete; outer cell walls of endodermis not thickened; vascular bundle single. Pollen cones crowded near the proximal end of a new shoot, forming more or less elongated "spikes," ellipsoid-cylindric, 10-15 mm long, yellowish when grown to full size. Microsporophyll peltate, rounded at the distal end, ca. 1 mm wide, smooth with entire margins. Seed cones concentrated at the ends of main branches, subterminal, solitary or in whorls of 2-4, erect on 5-12 cm long, 15-20 mm thick, bracteate peduncles until the beginning of the second season, becoming pendulous. Immature cones cylindrical, 25-50 mm long at the time of fertilization, growing to twice that size by the end of the first growing season, at first purplish, then greenish, very resinous, maturing in two seasons. Mature cones narrowly cylindrical when closed, straight or slightly curved, broadly cylindrical when opened, then 25-45 X 814 cm. Seed scales ca. 110-130, readily opening, patent or slightly reflexed, the basal sterile scales often more reflexed, angular-obovate to obtrullate, up to 40 mm wide and 4-5 mm thick, purplish brown abaxially, reddish brown with light brown marks of seed wings and shallow seed cavities on the adaxial side. Apophysis triangular to obtusely rhombic, 5-8 mm thick at base, straight, smooth or radially striated, yellowish brown, often with yellow resin clusters. Umbo terminal, obtuse-triangular, ca. 10 mm wide, concolorous or lighter than the apophysis. Seeds obovoid or obliquely obovoid, (10-) 12-15 (-18) X 6-10 mm, dark brown. Seed wings adnate, relatively short compared to size of seed scales, broadly obovoid to dolabriform or truncate, 20-30 X 12-15 mm, light brown. Cotyledons 11-18. Remarks on morphology. The above description pertains to Pinus lambertiana in Mexico only. Tree size here is considerably shorter (due to climatic conditions) than in the Sierra Nevada of California or the Cascade Range of Oregon, where this species grows to be the largest of all extant pines. Maximum height in the Sierra San Pedro Martir is given as 40 m by Minnich (1987); references to tree sizes of 60 m or more in Martínez (1948) and Perry (1991) undoubtedly pertain to the species outside of Mexico. A maximum cone size of 56 cm has also been reported from the United States (Kinloch & Scheuner in Burns & Honkala, 1990), and such large cones have not been found in Mexico.
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Discussion
Uses. Due to its restricted range in Mexico, this species is of little economic importance. Its remoteness has safeguarded the Mexican population from extensive logging in the past; a road onto the high plateaus has only recently been built. Most of the stands are now within the boundaries of the Sierra San Pedro Martir National Park.
The earliest collection of Pinus lambertiana south of the U.S.-Mexican border was made by T. S. Brandegee in May 1893, about 200 km S of the nearest stands in California. The species was discovered by David Douglas in August 1825, or perhaps October 1826, in Oregon and was formally described in a letter by Douglas, read on 6 November 1827 by the Secretary on the occasion of a meeting of the Linnean Society of London and subsequently published in the Transactions (Douglas, 1827). Original material is in K, in the herbaria of both J. D. Hooker and G. Bentham. Exactly when Douglas collected this material is not known, and the location is likewise vague. At any rate, “Lat. 43°” is not in California but in Oregon. Only small branchlets with foliage are preserved and no cones (as cited in the protologue). On the sheet ex herb. J. D. Hooker is mounted a third, later collection by J. M. Bigelow (in 1853-1854), which is not type material. The other two Douglas pieces are here designated as the lectotype.Minnich (1987) established the extent of this species in northern Baja California and confirmed the isolated disjunction of P. lambertiana. Silba (1990) described it as a distinct variety, with “more pectinately arranged, thicker, curved needles 41-67 mm long by 0.9 mm wide," based on only two studied collections, the type cited above and McGill & Pinkava P12325 (NY). The maximum leaf length measured on the type specimen is 82 mm; none of the characters are outside the range found in material from the United States.The amphistomatic leaves of P. lambertiana distinguish it from pines of the P. ayacahuite/P. strobiformis pair and seem to link it with the P. monticolal P. strobus pair, which does not support the scheme of relationships proposed by Martínez (1948). Its cone morphology takes it close to P. flexilis, as does its genetic affinity based on allozyme analysis (Krutovskii et al., 1994). Further study, including cpDNA analysis, to investigate these relationships is highly desirable. Phenology: Pollen dispersal was observed to occur in Michoacán at 1500 m near the end of February (Styles 24) and may occur up to a month later at high altitudes.Distribution and Ecology: United States: In Oregon and California mainly along the Cascade Range and in the Sierra Nevada, in S California scattered in high mountains. Mexico: In Baja California Norte, its only locality is the higher part of the Sierra San Pedro Martir, which is the southernmost occurrence of the species. Its altitudinal range there is 2200-2800 m, where it occurs frequently as a constituent of mixed conifer forest on sites with deepest soil, often along intermittent streams. Other conifers are Abies concolor, Pinus contorta var. murrayana, and P. jeffreyi. Annual precipitation is a modest 500 mm and winter snows and frosts are common. Phenology: Time of pollen dispersal is June-July.
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Distribution
United States of America North America| Oregon United States of America North America| Mexico North America| Baja California Mexico North America|