Range of Pinus occidentalis (1). Basemap from Expedia Maps. |
Pinus occidentalis
Swartz 1788
Common NamesTaxonomic notesSyn: P. occidentalis var. baorucoensis Silba 1985 (1).Description"Tree, medium to tall, height to 30-40 m, dbh to 100-120 cm. Trunk monopodial, erect, terete, usually slender, in forest stands with clear bole for 2/3-3/4 of height. Bark thick, on lower trunk 30-40 mm, rough, scaly, breaking into irregularly square plates divided by deep fissures, longitudinally fissured toward the base, on young trees and branches light brown, the lowcr crown curved and drooping, forming an irregular, open crown. Shoots uninodal, glaucous to pruinose in the first year, later very rough with large, short-decurrent, persistent pulvini, brown. Cataphylls slender, subulate to caudate, straight or recurved, scarious, with erose margins, brown, persisting some time after the leaf fascicles have fallen. Vegetative buds ovoid to ovoid-oblong, acute, the terminal bud 10-15 mm long, the laterals shorter, usually slightly resinous; the scales imbricate, more or less appressed, scarious, with ciliate margins, lustrous brown. Fascicle sheaths persistent, (8-)10-15 mm long, scales lustrous silvery-brown with erose-ciliate margins, weathering grey-brown. Leaves in fascicles of 3-5, in dense, spreading tufts at the ends of branches, persisting to the third year, straight or slightly curved, more or less rigid, (11-)14-18(-20) cm × 1.2-1.4 mm, with serrulate margins, acute, pungent, light green. Stomata on all faces of leaves, in 6-8 lines on the convex abaxial face and ca. 4 lines on each adaxial face. Leaf anatomy: Cross section triangular or transverse-triangular, with convex abaxial side; hypodermis multi-layered (3-4 rows of cells); resin ducts (2?-)3-5, internal; stele elliptic to transverse-obovate in cross section; outer cell walls of endodermis not thickened; vascular bundles 2, distinctly separate. Pollen cones clustered near the proximal end of a new shoot, cylindrical, often recurved when mature, 15-25 × 5 mm, pinkish yellow, turning yellowish brown. Seed cones subterminal, solitary or in pairs on 10-20 mm long, straight or recurved, bracteate peduncles, persisting several years after seed dispersal, falling with the peduncle attached. Immature cones ovoid to ovoid-attenuate when growing, 10-15 × 8-10 mm, with inflexed spines, ochraceous, maturing in two seasons. Mature cones ovoid to ovoid-conical, straight or curved, nearly symmetrical, large cones with a flattened base, (4-)5-9(-11) × 3.5-6.5 cm when open. Seed scales ca. 110-150, parting to release the seeds except those at the base, oblong, straight or recurved, thin woody, dark purplish brown abaxially, dark brown with indistinct lighter brown marks of seed wings on the adaxial side. Apophysis slightly raised, transversely keeled, rhombic to pentagonal in outline, up to 12 mm wide, on the proximal scales more or less gibbous, (lustrous) dark brown, radially striate, weathering dull grey. Umbo dorsal, raised and often curved, usually armed with an inflexed, 2-3 mm long spine, grey-brown. Seeds obliquely obovoid, flattened, 5-6 × 3-4 mm, light, mottled grey-brown. Seed wings articulate but effective, held to the seed by two claws, obliquely ovate or oblong, 12-18 × 4-6 mm, ochraceous with black or grey tinge or stripes" (1).RangeHispaniola: Haiti and the Dominican Republic at 200-3200 m in mixed or pure stands (1).Big TreeOldestDendrochronologyEthnobotanyObservationsI have a report of it in Puerto Rico, along Km.13-16 of Route 120, in Maricao Forest Reserve, where it may be introduced (2).RemarksCitations(1) Farjon & Styles 1997.(2) E-mail from Vladimir Dinets, 4-Jan-2000. |
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