Difference between revisions of "Pseudotsuga"
Traité Gén. Conif., ed. 2 256. 1867.
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Revision as of 18:57, 24 September 2019
Trees conic, evergreen. Bark initially smooth, with resin blisters; in age reddish brown, corky, furrowed. Branches often pendulous, irregularly whorled; short (spur) shoots absent; leaf scars transversely elliptic, slightly raised proximally but essentially flush with twig distally. Buds elongate, not resinous, apex acute. Leaves borne singly, persisting 6–8 years, alternate, short-stalked, flattened; resin canals 2, marginal. Cones borne on year-old twigs. Pollen cones axillary. Seed cones maturing first season, shed whole, deflexed or pendent, ellipsoid, ovoid, or cylindric, nearly sessile, lacking apophysis and umbo; scales persistent, apex rounded; bracts ± exserted, apex 3-lobed, lobes with acute apices, central lobe narrow, longer than lateral lobes. Seeds winged; cotyledons 6–12. x =12, 13.
Distribution
North America, 3 in e Asia.
Discussion
Species 5 (2 in the flora).
Selected References
Lower Taxa
Key
1 | Leaf apex mucronulate; seed cones 9-20 cm; sw California. | Pseudotsuga macrocarpa |
1 | Leaf apex obtuse to acute; seed cones 4-10 cm; widely distributed in w North America. | Pseudotsuga menziesii |