Pinus leiophylla var. chihuahuana

(Engelmann) G. R. Shaw

Pines Mexico 14, plate 7, figs. 10, 11. 1909.

Common names: Chihuahua pine pino real pino prieto
Illustrated
Basionym: Pinus chihuahuana in Wislizenus, Mem. Tour N. Mexico, 103. 1848
Treatment appears in FNA Volume 2.

Trees to 25m; trunk to 0.9m diam., slender; crown conic, becoming rounded. Bark brown to redbrown, narrowly furrowed, cross-checked into long, irregularly and narrowly rectangular, flat, scaly ridges. Branches ascending; twigs slender, orangebrown or glaucous and violet, aging redbrown, ±smooth or cracking. Buds ovoid, light-redbrown, ca. 0.6–0.7 (–1) cm, slightly resinous. Leaves (2–) 3 (–4) per fascicle, spreading-ascending, persisting 2 years, 6–15cm × 0.8–1mm, straight to slightly twisted, dull gray-green, all surfaces with fine stomatal lines, margins finely serrulate, apex acute to acuminate; sheath to 1.5cm, shed early and completely. Pollen cones broadly ellipsoid, ca. 10–15mm, brown or yellow. Seed-cones maturing in 3 years, shedding seeds soon thereafter but long-persistent, paired or solitary, symmetric, lateral, narrowly ovoid before opening, broadly ovoid to nearly globose when open, 3.5–5 (–9) cm, chestnut-brown or greenish brown, aging gray to gray-brown, stalks to 1.5cm; apophyses slightly thickened and raised, not keeled; umbo central, slightly raised or depressed, with short, often deciduous prickle or unarmed. Seeds obovoid; body ca. 2mm, gray, mottled darker; wing ca. 10mm, dark-lined. 2n =24.


Habitat: Dry slopes and plateaus
Elevation: 1500–2500m

Discussion

Pinus leiophylla var. chihuahuana is one of the few pines that produce sprouts from stumps. It differs from the type variety in its dark, less roughened bark, its shorter range of leaf length, and its slightly broader leaves that occur more consistently in threes. (The narrower, often longer leaves of the type variety are in fours and fives.)

The type variety, Pinus leiophylla var. leiophylla, is exclusively Mexican.

Selected References

None.

Lower Taxa

None.

"relatively thin" is not a number.

resinous +
acute +  and acuminate +
not keeled +
Robert Kral +
(Engelmann) G. R. Shaw +
brown;redbrown +
rectangular +
Pinus chihuahuana +
mottled darker +  and gray +
2 cm20 mm <br />0.02 m <br /> (?) +
0.7 cm7 mm <br />0.007 m <br /> (1 cm10 mm <br />0.01 m <br />) +
resinous +
light-redbrown +
conspicuous +
0.6 cm6 mm <br />0.006 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
Chihuahua pine +, pino real +  and pino prieto +
5 cm50 mm <br />0.05 m <br /> (9 cm90 mm <br />0.09 m <br />) +
gray;gray-brown +
3.5 cm35 mm <br />0.035 m <br /> (5 cm50 mm <br />0.05 m <br />) +
long-persistent +
broadly ovoid +  and nearly globose +
rounded +  and conic +
Ariz. +, N.Mex. +  and Mexico +
1500–2500m +
sheathed +  and sessile +
rounded +, 2-3-angled +  and terete +
Dry slopes and plateaus +
arranged +  and fascicles +
gray-green +
straight +
persisting +
6 cm60 mm <br />0.06 m <br /> (15 cm150 mm <br />0.15 m <br />) +
spreading-ascending +
2 (?) +  and 3 (?) +
scale-like +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
not winged +  and 2-winged +
yellow +  and brown +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
Pines Mexico +
fibrous;woody +
arranged +  and overlapping +
persistent +
flattened +
pliable +  and woody +
grouped +  and solitary +
long-persistent +
wingless +, winged +, stalked +  and sessile +
persistent +
pendent;more or less erect +
obovoid +
0 cm0 mm <br />0 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
reduced;well-defined short +
Illustrated +
extended +
Apinus +, Strobus +  and Caryopitys +
Pinus leiophylla var. chihuahuana +
Pinus leiophylla +
variety +
decurrent +  and elongate +
slender +
redbrown +, violet +  and orangebrown +
slender +
depressed +
dark-lined +
reduced +
10 cm100 mm <br />0.1 m <br /> (?) +