Pinus ponderosa </i> subsp. <i>brachyptera description

Pinus ponderosa subsp. brachyptera (Engelmann) E. Murray

Common Names

Rocky Mountain yellow pine (2), Rocky Mountain ponderosa pine (1).

Taxonomic notes

Although here treated as a subspecies, this taxon is yet to be formally published as a subspecies within P. ponderosa. It was separately described in 1848 as Pinus brachyptera Engelmann.

Many authorities (e.g., (1)) assign both P. ponderosa subsp. brachyptera and P. ponderosa subsp. scopulorum to a single taxon, P. ponderosa var. scopulorum. However, the two subspecies are readily distinguished on the basis of number of needles per fascicle (normally three in this taxon, but two in subsp. scopulorum) and cone characters (see description below).

This subspecies intergrades with subsp. scopulorum at the northern limits of its range, and with Pinus arizonica in Arizona, New Mexico, and south just into Sonora in Mexico (1; also refs. 6-9 under P. ponderosa main page).

Description

Trees to 24 m tall and 1.5 m diam. Twigs mostly red-brown, rarely glaucous. Leaves mainly 3 per fascicle, 10-17 cm × 1.4-2 mm. "Pollen cones yellow. Seed cones mostly symmetric, 5-10 cm; apophyses of fertile scales moderately raised; umbo low pyramidal, narrowing acuminately to a stout-based prickle or short sharp spur. Seed body 3-4 mm; wing to 15 mm" (1). Cones are slightly larger and more glossy in texture than those of subsp. scopulorum.

Range

USA: New Mexico and Arizona; Mexico: N Sonora.

Big Tree

Oldest

Probably a specimen from the Malpais Lava Beds National Monument.

Dendrochronology

Ethnobotany

Observations

Widely enountered throughout most of its range. In my experience, especially noteworthy occurrences include: (a) the Malpais Lava Beds National Monument of New Mexico, where some of the oldest known trees are found and (b) the plateaus of northern Arizona and New Mexico, where ponderosa provided the forests that were used in building the Anasazi civilization 900 years ago.

Remarks

Citations

(1) Kral in Flora of North America online.
(2) Peattie 1950.
(3) Little 1980.
(4) American Forests 1996.
(5) Brown 1996.
(6) Farjon & Styles 1997.