Pinus monophylla |
Pinus washoensis |
|
---|---|---|
piñón, single leaf pinyon, single-leaf pine, singleleaf pinyon pine |
Washoe pine |
|
Habit | Trees to 14m; trunk to 0.5m diam., strongly tapering, much branched; crown usually rounded, dense. | Trees to 60m; trunk to 1m diam., straight; crown pyramidal. |
Bark | red-brown, irregularly furrowed or cross-checked, scaly. |
yellow-brown to reddish, fissured, plates scaly. |
Branches | spreading and ascending, persistent to near trunk base; twigs stout, orange-brown, aging brown to gray, sometimes sparsely puberulent. |
spreading-ascending; twigs stout, orangish, aging gray, rough. |
Buds | ellipsoid, light red-brown, 0.5–0.7cm, resinous; scale margins fringed. |
ovoid, red-brown, 1.5–2cm, not resinous; scale margins fringed. |
Leaves | 1(–2) per fascicle, ascending, persisting 4–6(–10) years, 2–6cm × 1.3–2(–2.5)mm, curved, terete (though often 2-grooved), gray-green, all surfaces with stomatal lines, margins entire, apex subulate; sheath 0.5–1cm, scales soon recurved, forming rosette, shed early. |
(2–)3 per fascicle, spreading-ascending, persisting (2–)4–6(–7) years, 10–15cm × ca. 1.5mm, slightly twisted, gray-green, all surfaces with stomatal lines, margins finely serrulate, apex acuminate; sheath 1–2cm, base persistent. |
Pollen cones | ellipsoid, ca. 10mm, yellow. |
cylindric, 10–20mm, red-purple. |
Seed(s) | cones maturing in 2 years, shedding seeds and falling soon thereafter, spreading, symmetric, ovoid before opening, broadly depressed-ovoid to nearly globose when open, 4–6(–8)cm, pale yellow-brown, nearly sessile; apophyses thickened, slightly raised; umbo subcentral, raised or depressed, nearly truncate, apiculate. |
cones maturing in 2 years, shedding seeds soon thereafter, not persistent, spreading, slightly asymmetric, ovoid-conic before opening, broadly ovoid when open, 7–10cm, tan or pale red-brown, sessile, abaxial surface of scales darker and sharply contrasting in color with adaxial surface; apophyses slightly raised, low pyramidal; umbo central, narrowly pyramidal, tapering into short, reflexed, fine prickle. |
2n | =24. |
=24. |
Pinus monophylla |
Pinus washoensis |
|
Habitat | Dry low-montane or foothill pinyon-juniper woodland | Dry montane forests |
Elevation | 1000–2300m (3300–7500ft) | 2100–2500m (6900–8200ft) |
Distribution |
AZ; CA; ID; NV; UT; Mexico in Baja California
|
CA; NV |
Discussion | Pinus monophylla hybridizes with P. edulis and P. quadrifolia. Singleleaf pinyon (Pinus monophylla) is the state tree of Nevada. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Pinus washoensis often occurs in large stands and resembles P. jeffreyi. The number and posture of seed-cone scales fall within the ranges given for P. jeffreyi. The abaxial surface of these scales has a significantly darker pigmentation, however; such a color contrast is not apparent in P. jeffreyi. Forest geneticists have developed hybrids between P. washoensis and related yellow pines, but no natural hybrids have been observed. Some workers regard P. washoensis as closely related to—or even conspecific with--- P. ponderosa. Of conservation concern. (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 | Caryopitys monophylla, P. californiarum, P. cembroides var. monophylla | |
Name authority | Torrey & Frémont: in Frémont, Rep. Exped. Rocky Mts. 2: 319, plate 4. (1845) | H. Mason & Stockwell: Madroño 8: 62. (1945) |
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