Pinus strobiformis |
Pinus echinata |
|
---|---|---|
Chihuahua white pine, Mexican white pine, pino enano, Southwestern white pine |
shortleaf pine |
|
Habit | Trees to 30m; trunk to 0.9m diam., slender, straight; crown conic, becoming rounded to irregular. | Trees to 40m; trunk to 1.2m diam., straight; crown rounded to conic. |
Bark | gray, aging red-brown, furrowed, with narrow, irregular, scaly ridges. |
red-brown, scaly-plated, plates with evident resin pockets. |
Branches | spreading-ascending; twigs slender, pale red-brown, puberulous or glabrous, sometimes glaucous, aging gray or gray-brown, smooth. |
spreading-ascending; 2-year-old branchlets slender (ca. 5mm or less), greenish brown to red-brown, often glaucous, aging red-brown to gray, roughened and cracking below leafy portion. |
Buds | ellipsoid, red-brown, ca. 1cm, resinous. |
ovoid to cylindric, red-brown, 0.5–0.7(–1)cm, 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. |
2(–3) per fascicle, spreading-ascending, persistent 3–5 years, (5–)7–11(–13)cm × ca. 1mm, straight, slightly twisted, gray- to yellow-green, all surfaces with fine stomatal lines, margins finely serrulate, apex abruptly acute; sheath 0.5–1(–1.5)cm, base persistent. |
Pollen cones | cylindric, ca. 6–10mm, pale yellow-brown. |
cylindric, 15–20mm, yellow- to pale purple-green. |
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, semipersistent, solitary or clustered, spreading, symmetric, lanceoloid or narrowly ovoid before opening, ovoid-conic when open, 4–6(–7)cm, red-brown, aging gray, nearly sessile or on stalks to 1cm, scales lacking contrasting dark border on adaxial surfaces distally; umbo central, with elongate to short, stout, sharp prickle. |
2n | =24. |
=24. |
Pinus strobiformis |
Pinus echinata |
|
Habitat | Arid to moist summit elevations, montane forests | Uplands, dry forests |
Elevation | 1900–3000m (6200–9800ft) | 200–610m (700–2000ft) |
Distribution |
AZ; NM; TX; n Mexico
|
AL; AR; DE; FL; GA; IL; KY; LA; MD; MO; MS; NC; NY; OH; OK; PA; SC; TN; TX; VA; WV
|
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.) |
Although Pinus echinata is highly valued for timber and pulpwood, it is afflicted by root rot. It hybridizes with P. taeda, the pine most commonly associated with it. (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 | |
Name authority | Engelmann: in Wislizenus, Mem. Tour N. Mexico 102. (1848) | Miller: Gard. Dict., ed. 8 Pinus no. 12. (1768) |
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