Pinus ponderosa var. arizonica
Pines Mexico 24, plates 4, 17, fig. 4. 1909.
Trees to 30m; trunk to 1.2m diam. Twigs mostly purple or red-brown, 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
Ariz., N.Mex., Mexico.
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.