Pinus attenuata |
Pinus albicaulis |
|
---|---|---|
knobcone pine |
pine à blanche écorce, scrub pine, white-bark pine |
|
Habit | Shrubs or trees to 24m; trunk to 0.8m diam., usually straight; crown mostly narrowly to broadly conic. | Trees to 21m; trunk to 1.5m diam., straight to twisted and contorted; crown conic, becoming rounded to irregularly spreading. |
Bark | purple-brown to dark brown, shallowly and narrowly fissured, with irregular, flat, loose-scaly plates, on upper sections of trunk nearly smooth. |
pale gray, from distance appearing whitish to light gray and smooth, in age separating into thin plates. |
Branches | ascending; twigs slender, red-brown. |
spreading to ascending, often persistent to trunk base; twigs stout, pale red-brown, with light brown, often glandular puberulence, somewhat roughened by elevated scars, aging gray to pale gray-brown. |
Buds | ovoid to ovoid-cylindric, dark red-brown, aging darker, ca. 1.5cm, resinous; scale margins fringed, apex attenuate. |
ovoid, light red-brown, 0.8–1cm; scale margins entire. |
Leaves | 3 per fascicle, spreading or ascending, persisting 4–5 years, (8–)9–15(–20)cm × (1–)1.3–1.8mm, straight or slightly curved, twisted, yellow-green, all surfaces with fine stomatal lines, margins serrulate, apex abruptly conic-subulate; sheath (1–)1.5–2cm, base persistent. |
5 per fascicle, mostly ascending and upcurved, persisting 5–8 years, 3–7cm × 1–1.5(–2)mm, mostly connivent, deep yellow-green, abaxial surface less so, adaxial surface conspicuously whitened by stomates, margins rounded, minutely serrulate distally, apex conic-acute; sheath 0.8–1.2cm, shed early. |
Pollen cones | ellipsoid-cylindric, 10–15mm, orange-brown. |
cylindro-ovoid, ca. 10–15mm, scarlet. |
Seed(s) | cones maturing in 2 years, serotinous, long-persistent, remaining closed for 20 years or more, or opening on burning, in whorls, hard and heavy, very asymmetric, lanceoloid before opening, ovoid-cylindric when open, 8–15cm, yellow- or pale red-brown, stalks to 1cm; apophyses toward outside base increasingly elongate, mammillate or raised-angled-conic, downcurved near base, scarcely raised on branchlet side, rhombic; umbo central, low-pyramidal, sharp, upcurved. |
cones remaining on tree (unless dislodged by animals), not opening naturally but through animal agency, spreading, symmetric, broadly ovoid to depressed-ovoid or nearly globose, 4–8cm, dull gray- to black-purple, sessile to short-stalked; scales thin-based and easily broken off; apophyses much thickened, strongly cross-keeled, tip upcurved, brown; umbo terminal, short, incurved, broadly triangular, tip acute. |
2n | =24. |
=24. |
Pinus attenuata |
Pinus albicaulis |
|
Habitat | Fire successional on dry slopes and foothills of Sierra Nevada and the Cascade and Coast ranges | Thin, rocky, cold soils at or near timberline, montane forests |
Elevation | 300–1200m (1000–3900ft) | 1300–3700m (4300–12100ft) |
Distribution |
CA; OR; Mexico in Baja California
|
CA; ID; MT; NV; OR; WA; WY; AB; BC
|
Discussion | Pinus attenuata, mostly a chaparral species, bears cones at an early age. Its seed crops are heavy, and a hot fire permits the seeds to be released. It forms hybrids with P. muricata and P. radiata. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Although two reliable dendrologists, G. B. Sudworth (1917) and N. T. Mirov (1967), include Utah in the distribution of Pinus albicaulis, more recent workers have not found it to occur there. The fresh-cut wood of Pinus albicaulis is sweet-scented. Seeds are dispersed mainly by Clark's nutcracker [Nucifraga columbiana (Wilson), family Corvidae]. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 2. | FNA vol. 2. |
Parent taxa | Pinaceae > Pinus | Pinaceae > Pinus |
Sibling taxa | ||
Synonyms | P. tuberculata | Apinus albicaulis |
Name authority | Lemmon: Mining Sci. Press 64: 45. (1892) | Engelmann: Trans. Acad. Sci. St. Louis 2: 209. (1863) |
Web links |
|