Pinus monophylla description

Tree on Cerro Teta de la India in Baja California Norte [C.J. Earle, Mar-2001].

Bark on a tree in the White Mountains, California. Width of view about 30 cm [C.J. Earle, 27-Mar-1987].

Foliage and seed-bearing cones on a tree in the White Mountains, California. Width of view about 15 cm [C.J. Earle, 27-Mar-1987].

Seedling and seed in the White Pine Mountains, Nevada. [C.J. Earle, 25-Sep-2001].

Pinus monophylla Torrey et Frémont 1845

Common Names

Singleleaf piñon (Arno & Gyer 1973); one-leaved, Gray, Frémont, or Nevada nut pine (Peattie 1950).

Taxonomic notes

Subsection Cembroides (Perry 1991). Syn: Caryopitys monophylla (Torrey & Frémont) Rydberg; Pinus californiarum D.K. Bailey; P.cembroides Zuccarini var. monophylla (Torrey & Frémont) Voss (Silba 1986).

Description

Trees 5-9(14) m tall and up to 50 cm diameter, strongly tapering, much branched; crown usually rounded, dense. Bark red-brown, irregularly furrowed or cross-checked, scaly. Branches spreading and ascending, persistent to near trunk base; twigs stout, orange-brown, aging brown to gray, sometimes sparsely puberulent. Buds ellipsoid, light red-brown, 0.5-0.7 cm, resinous; scale margins fringed. Needles 1 (rarely 2) per fascicle, ascending, persisting 4-6(10) years, 2-6 cm x 1.3-2(2.5) mm, stout, curved, terete (though often 2-grooved), gray-green, all surfaces with stomatal lines, margins entire, apex subulate; sheath 0.5-1 cm, scales soon recurved, forming rosette, shed early. Staminate cones ellipsoid, ca. 10 mm, yellow. Ovulate cones maturing in 2 years, shedding seeds and falling soon thereafter, spreading, symmetric, ovoid before opening, broadly depressed-ovoid to nearly globose when open, 4-6(8) cm, pale yellow-brown, nearly sessile; apophyses thickened, slightly raised; umbo subcentral, raised or depressed, nearly truncate, apiculate. As with other piñons, the seeds rest in a deep cone-scale declivity and upper cone scale tissue holds the seeds in place, so seeds do not readily fall out and are readily available to avian dispersers. Seeds cylindric-ellipsoid; body 15-20mm, gray-brown to brown, wingless, edible. 2n=24 (Little 1980, Kral 1993, Lanner 1999).

Range

USA: Idaho, Utah, Nevada, Arizona, California; Mexico: Baja California Norte. 1000-2300 m. Prefers dry, gravelly slopes in semiarid country, where it forms woodlands alone or with juniper (Juniperus sp.) (Little 1980, Kral 1993). You can download a high-quality species distribution map at http://www.usgs.nau.edu/global_change/RangeMaps.html (link checked 2006.03.30). See also Thompson et al. (1999).

Big Tree

Diameter 133 cm, height 14 m, crown spread 12 m, located in Inyo County, California (American Forests 1996).

Oldest

Tree PGH-02 collected in the Pine Grove Hills of Nevada by Franco Biondi and S. Strachan had a crossdated age of 888 years (RMTRR 2006).

Dendrochronology

Has been used in stable-isotope studies, historical archeology (dating the construction of old mine buildings), air pollution assessment, and a wide variety of climate studies (Bibliography of Dendrochronology). NOAA lists 15 chronologies for this species (NOAA Tree Ring Search Page).

Ethnobotany

The large, nutritious seeds were a staple food for native americans living within the range of this species.

Observations

Seen widely throughout its range. Piñon-juniper woodlands are particularly widespread and well-developed in east-central Nevada, while the largest and most impressive individual trees I have seen have been in Joshua Tree National Park (CA), near the southwest range limits of the species.

Remarks

The only pine bearing a single needle per fascicle.

Hybridizes with P. edulis and P. quadrifolia (Kral 1993).

Singleleaf piñon is the state tree of Nevada (Kral 1993).

Citations

Lanner, Ronald M. E-mail 20-Dec-1999.