Pinus strobiformis |
Pinus quadrifolia |
|
---|---|---|
Chihuahua white pine, Mexican white pine, pino enano, Southwestern white pine |
four-needle pinyon, nut pine, Parry pine, Parry pinyon, Parry pinyon pine, piñón, piñón de California |
|
Habit | Trees to 30m; trunk to 0.9m diam., slender, straight; crown conic, becoming rounded to irregular. | Trees to 10m; trunk to 0.5m diam., straight, much branched; crown dense, becoming rounded. |
Bark | gray, aging red-brown, furrowed, with narrow, irregular, scaly ridges. |
red-brown, irregularly furrowed and cross-checked to irregularly rectangular, plates scaly. |
Branches | spreading-ascending; twigs slender, pale red-brown, puberulous or glabrous, sometimes glaucous, aging gray or gray-brown, smooth. |
spreading to ascending, persistent to trunk base; twigs slender, pale orange-brown, puberulent-glandular, aging brown to gray-brown. |
Buds | ellipsoid, red-brown, ca. 1cm, resinous. |
ovoid, light red-brown, ca. 0.4–0.5cm, slightly resinous. |
Leaves | 5 per fascicle, spreading to ascending-upcurved, persisting 3–5 years, 4–9cm × 0.6–1mm, straight, slightly twisted, pliant, dark green to blue-green, abaxial surface without evident stomatal lines, adaxial surfaces conspicuously whitened by narrow stomatal lines, margins sharp, razorlike and entire to finely serrulate, apex narrowly acute to short-subulate; sheath 1.5–2cm, shed early. |
(3–)4(–5) per fascicle, persisting 3–4 years, (2–)3–6cm × (1–)1.2–1.7mm, curved, connivent, stiff, green to blue-green, margins entire to minutely scaly-denticulate, finely serrulate, apex subulate, adaxial surfaces mostly strongly whitened with stomatal bands, abaxial surface not so but 2 subepidermal resin bands evident; sheath 0.5–0.6cm, scales soon recurved, forming rosette, shed early. |
Pollen cones | cylindric, ca. 6–10mm, pale yellow-brown. |
ovoid, ca. 10mm, yellowish. |
Seed(s) | cones maturing in 2 years, shedding seeds and falling soon thereafter, pendent, symmetric, lance-cylindric before opening, broadly lance-cylindric when open, 15–25cm, creamy brown to light yellow-brown, stalks to 6cm; apophyses somewhat thickened, strongly cross-keeled, tip reflexed; umbo terminal, low. |
cones maturing in 2 years, shedding seeds and falling soon thereafter, spreading, symmetric, ovoid before opening, broadly ovoid to depressed-globose when open, (3–)4–8(–10)cm, pale yellow-brown, sessile to short-stalked, apophyses thickened, strongly raised, diamond-shaped, transversely keeled, umbo subcentral, low-pyramidal or sunken, blunt. |
2n | =24. |
|
Pinus strobiformis |
Pinus quadrifolia |
|
Habitat | Arid to moist summit elevations, montane forests | Dry rocky sites |
Elevation | 1900–3000m (6200–9800ft) | 1200–1800m (3900–5900ft) |
Distribution |
AZ; NM; TX; n Mexico
|
CA; Mexico in Baja California
|
Discussion | In the northern part of the range, Pinus strobiformis overlaps P. flexilis and reportedly hybridizes with it. On average P. strobiformis has longer, more slender leaves and thinner, more spreading-tipped apophyses than are found in P. flexilis, and stomatal bands are not evident on the abaxial surface of its leaves. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Pinus quadrifolia is the rarest pinyon in the flora. It hybridizes naturally with P. monophylla. (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. ayacahuite var. brachyptera, P. ayacahuite var. reflexa, P. ayacahuite var. strobiformis, P. flexilis var. reflexa, P. reflexa | P. cembroides var. parryana, P. juarezensis, P. parryana |
Name authority | Engelmann: in Wislizenus, Mem. Tour N. Mexico 102. (1848) | Parlatore ex Sudworth: U.S.D.A. Div. Forest. Bull. 14: 17. (1897) |
Web links |