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Pinus ponderosa subsp. benthamiana not yet formally described
Common NamesPonderosa pine (1), Pacific race ponderosa.Taxonomic notesAlthough here treated as a subspecies, this taxon is yet to be formally published as a subspecies within P. ponderosa. It was separately described in 1847 as Pinus benthamiana Hartweg.It is locally sympatric with and occasionally hybridizes with P. jeffreyi, but hybrids are rare and in areas of sympatry it usually occurs at lower elevations than P. jeffreyi (1). Description"Trees to 72 m; trunk to 2.5 m diam. Twigs commonly red-brown, not glaucous. Buds very resinous. Leaves mainly 3 per fascicle, 12-25(-30) cm x (1.2-)1.5-2 mm. Pollen cones mostly red. Seed cones 8-15 cm, symmetric; apophyses of fertile scales moderately raised; umbo low-pyramidal, tapering acuminately to short broad-based prickle. Seed body 6-9 mm; wing 15-25 mm" (1).RangeUSA: Washington and Oregon west of the Cascade crest, California, particularly in the Sierra Nevada but also in a few areas in the Coast Ranges; south nearly to the Mexican border (M.P. Frankis, pers. comm. Dec-1998). Habitat montane, dry, open forests at 0-2300 m (1).Big TreeHeight 68 m, dbh 232 cm, crown spread 21 m, in Plumas National Forest, CA (2). Height 78.9 m and dbh 171 cm at Big Pine Campground, Siskiyou National Forest, OR (4).OldestDendrochronologyEthnobotanyA valuable timber tree, the harvest of which far exceeds regrowth because of high timber value and multiple uses of the wood (1).ObservationsSince the species is so common within its range, only a few choice locales can be mentioned here. It can be seen at low montane elevations in Sequoia, Kings Canyon and Yosemite National Parks and in Calaveras Big Trees State Park, all in California. The Calaveras forests are particularly noteworthy because a prescribed fire program has been implemented in the park. Consequently, the stands include examples of open pine forest understory with pine seedling regeneration. Such a sight has not been seen in many American ponderosa stands this century, due to widespread fire suppression that seems to have doomed many of our finest ponderosa forests to replacement by more shade-tolerant conifers such as Abies grandis. The pine forests of California were eloquently described by John Muir (5). At Fort Lewis, Washington, it grows west of the Cascade Mountains due to edaphic drought conditions created by an extremely porous glacial outwash substrate.RemarksIt is the largest and stateliest yellow pine in North America (1).Citations(1) Kral in Flora of North America online.(2) American Forests 1996. (3) E-mail communication from Robert Van Pelt, who measured these trees; 18-Mar-1998. (4) E-mail communication from Robert Van Pelt, who measured this tree; 22-Jul-1999. (5) Muir 1894. (6) Hickman 1993. See also: |
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