Pinus ponderosa var. arizonica

(Engelmann) Shaw

Pines Mexico 24, plates 4, 17, fig. 4. 1909.

Common names: Arizona pine
Basionym: Pinus arizonica in Rothrock, Wheeler, U.S. Geogr. Surv. West 100th Merid. Rep. 6: 260. 1878
Treatment appears in FNA Volume 2.

Trees to 30m; trunk to 1.2m diam. Twigs mostly purple or redbrown, usually glaucous. Buds slightly resinous. Leaves mainly 4–5 per fascicle, 7–17cm × 1–1.2 (–1.5) mm. Pollen cones mostly yellow. Seed-cones often asymmetric, 5–8cm; apophyses at abaxial base often strongly raised, frequently mammillate; umbo low, broadly pryamidal, and merely acute or with very short apiculus. Seed body 3–4mm; wing to 15mm. 2n =24.


Habitat: Slopes, canyons and rims, and tablelands
Elevation: 2100–2500m

Discussion

The least common, least accessible ponderosa pine in the flora is Pinus ponderosa var. arizonica. It has leaves ranging widely in number per fascicle and in length, perhaps an expression of intergradation with P. ponderosa var. scopulorum, with which it is sympatric over broad areas.

Texas (Chisos Mountains) pines that are referred by some workers to P. ponderosa var. arizonica, belong to P. ponderosa var. scopulorum.

Selected References

None.

Lower Taxa

None.

"relatively thin" is not a number.

resinous +
acuminate +  and acute +
mammillate +
Robert Kral +
(Engelmann) Shaw +
yellow;redbrown +
persistent +
Pinus arizonica +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
mottled darker +, brown +  and yellowbrown +
0.4 cm4 mm <br />0.004 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
descending +  and spreading-ascending +
resinous +
conspicuous +
0 cm0 mm <br />0 m <br /> (2 cm20 mm <br />0.02 m <br />) +
1 cm10 mm <br />0.01 m <br /> (?) +
Arizona pine +
sessile +  and nearly sessile +
reddish-brown +
5 cm50 mm <br />0.05 m <br /> (8 cm80 mm <br />0.08 m <br />) +
spreading +  and reflexed +
ovoid +  and conic-ovoid +
symmetric to slightly +
broadly conic +  and rounded +
Ariz. +, N.Mex. +  and Mexico +
2100–2500m +
sheathed +  and sessile +
rounded +, 2-3-angled +  and terete +
Slopes, canyons and rims, and tablelands +
arranged +  and fascicles +
25 cm250 mm <br />0.25 m <br /> (30 cm300 mm <br />0.3 m <br />) +
0.12 cm1.2 mm <br />0.0012 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
yellow-green +
persisting +
7 cm70 mm <br />0.07 m <br /> (17 cm170 mm <br />0.17 m <br />) +
spreading;erect +
4 (?) +  and 5 (?) +
scale-like +
0.1 cm1 mm <br />0.001 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
0 cm0 mm <br />0 m <br /> (1 cm10 mm <br />0.01 m <br />) +
rectangular +
not winged +  and 2-winged +
ellipsoid-cylindric +
1.5 cm15 mm <br />0.015 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
Pines Mexico +
fibrous;woody +
adjacent +  and separate +
persistent +
white-fringed +
reflexed +  and spreading +
flattened +
pliable +  and woody +
grouped +  and solitary +
long-persistent +
wingless +, winged +, stalked +  and sessile +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
persistent +
pendent;more or less erect +
ellipsoid-obovoid +
1.5 cm15 mm <br />0.015 m <br /> (3 cm30 mm <br />0.03 m <br />) +
reduced;well-defined short +
Illustrated +
extended +
Apinus +, Strobus +  and Caryopitys +
Pinus ponderosa var. arizonica +
Pinus ponderosa +
variety +
decurrent +  and elongate +
straight +
redbrown +  and purple +
with very short apiculus +, acute +  and pryamidal +
reduced +
0 cm0 mm <br />0 m <br /> (?) +  and 1.5 cm15 mm <br />0.015 m <br /> (?) +