Pinus sabiniana (gray pine) description

Pinus sabiniana

Douglas ex D.Don in Lambert 1832

Common names

Gray pine (most common), ghost pine, foothills pine; older sources may also call it digger, Sabine, bull, or grayleaf pine. For many years it was generally named digger pine due to its wide use by Native American tribes collectively and colloquially referred to as "diggers." However, that term has fallen into disgrace. As explained by Hunter (1991): "many Native Americans find the term digger offensive. A spokesman, who requests anonymity, for the California State Native American Heritage Commission says, "The word `digger' is very derogatory and insulting to California Indian people." A historical interpreter, who also requests anonymity, for the California State Indian Museum in Sacramento agrees: "To call a California Indian a 'digger' means you are either ignorant or you are purposely trying to insult him. It is a very derisive word."

Taxonomic notes

A member, along with two other California species (Pinus coulteri and Pinus torreyana), of subsection Sabinianae Loudon.

Some authorities spell the epithet "sabineana." This is an alternative, but not required spelling under Recommendation 60C of the International Code of Botanical Nomenclature. The merits of this spelling are debatable, and warrant a digression into the history of the name.

The species was described by David Douglas as Pinus sabinii, which is not grammatically correct Latin. This appears to be a conjugation of Sabinius, which was the Latinized form of Sabine's name. At the time it was commonly regarded as honorific to Latinize a scientist's name, so it is quite probable, given Douglas' deep respect for Sabine (see Aside, below), that he intended to commemorate Sabinius rather than plain old Joe Sabine.

It is also worth considering that the epithet "sabiniana" is to be found in literally thousands of references in both popular and common literature and thus should not be changed without a very good reason. On occasion the ICBN has determined to conserve an incorrect name simply on the basis of such long-standing and widespread use. Certainly, we can ask for a better reason to rename this species than "because it's not prohibited."

Aside: Douglas' journals left much evidence of his respect for Sabine (a respect which, alas, seems not to have been sincerely reciprocated; but that's another story). Consider his comment on July 24, 1824: "After several weeks’ preparation for a voyage to the Columbia river on the west coast of North America, on the afternoon of Saturday parted with J. Sabine, Esq., and all other friends." A month later he wrote Sabine a letter from Madeira, in September he called upon a friend of Sabine's in Rio de Janeiro. In June of 1825, he found a fine Phlox, an "exceedingly beautiful species I name P. Sabinii, in honour of Jos. Sabine, Esq." Throughout his journeys in North America, his journals are filled with references to Sabine, who is always first when he names the letters he must dispatch.

Description

Trees 12-21(25) m with diameters of 60-120 cm, straight to crooked, often forked; crown conic to raggedly lobed, sparse. Bark dark brown to near black, irregularly and deeply furrowed, ridges irregularly rectangular or blocky, scaly, often breaking away, bases of furrows and underbark orangish. Branches often ascending; cone-bearing branchlets stout, twigs comparatively slender, both pale purple-brown and glaucous, aging gray, rough. Buds ovoid, red-brown, ca. 1cm, resinous; scale margins white-fringed. Leaves mostly 3 per fascicle, drooping, persisting 3-4 years, 15-32 cm × 1.5 mm, slightly twisted, dull blue-green, all surfaces with pale, narrow stomatal lines, margins serrulate, apex short-acuminate; sheath to 2.4 cm, base persistent. Staminate cones ellipsoid, 10-15 mm, yellow. Ovulate cones maturing in 2 years, shedding seeds soon thereafter, persisting to 7 years, pendent, massive, heavy, nearly symmetric, ovoid before opening, broadly to narrowly ovoid or ovoid-cylindric when open, 15-25 cm, dull brown, resinous, stalks to 5cm. Scales long, thick, sharply keeled and 4-sided; apophyses elongate, curved, continuous with umbos to form long, upcurved claws to 2 cm. Seeds narrowly obovoid, thick-walled; body ca. 20 mm (largest in the genus), dark brown; wing broad, short, ca. 10 mm, shed easily. 2n=24 (Little 1980, Kral 1993). See García Esteban et al. (2004) for a detailed characterization of the wood anatomy.

Distribution and Ecology

USA: California through the Coast Ranges and the Sierra Nevada, nearly ringing the Central Valley, in dry foothills; Oregon, local in Douglas, Jackson and Josephine counties. Found at (30)300-900(1900) m elevation (Little 1980, Kral 1993, records of the Consortium of Pacific Northwest Herbaria searched 2009.06.16, and David Landrum email 2012.03.31). Commonly found in association with California blue oak (Quercus douglasii) or canyon live oak (Quercus chrysolepis). The climate is Mediterranean, with annual mean precipitation of 530 mm, ranging from 76 to 1,000 mm. Eighty percent of precipitation occurs during winter and early spring. Snow falls occasionally. The annual mean temperature is 16°C, with maximum summer temperatures sometimes above 41°C). Relative humidity is often 5 percent or lower in summer (FEIS database, 2004.03.02). Hardy to Zone 8 (cold hardiness limit between -12.1°C and -6.7°C) (Bannister and Neuner 2001). See also Thompson et al. (1999).

Distribution data from USGS (1999), updated to include more recent documentation of the species in Oregon.

Foothills pine and four species of Quercus (oaks) comprise the dominant species of the blue oak woodland, a community that essentially encircles California's Central Valley. There are few shrubs, and the understory consists mainly of introduced grasses and native forbs. As such, the woodland is slightly hotter and drier than the chaparral, with which it forms a landscape mosaic that also includes parklands and grasslands. At increasing elevations, foothills pine is restricted to open habitats on serpentine soils, being competitively displaced by Pinus coulteri and P. ponderosa subsp. benthamiana (Barbour 1988). The role of fire in the establishment and perpetuation of foothills pine has not been widely studied, but the species' fecundity, short life span and occurrence in fire-prone areas all suggest that it has coevolved with relatively frequent fire. However, fire can extirpate an isolated grove of the trees, and their range appears to have increased with anthropogenic fire suppression in California's Central Valley (Callahan 2009).

As with all other pines having large seeds with vestigial wings, this species relies on corvids to gather its seeds and plant them in suitable locations. In this case the principal actors are the Steller's jay and the scrub jay. The Steller's jay lives in forests and dense woodland and is a great flier, likely carrying the seeds for distances of some kilometers. In contrast, the scrub jay lives in the chaparral and in open country, but it usually does not carry seeds far from the tree, and is thus of limited value in reestablishing groves that have been destroyed by fire (although long seed longevity and the sturdy nature of the cones facilitate reestablishment from seed after fire). The contrasting ecology of these species may explain why this is a species of the foothills, not ranging far from the mountains (Callahan 2009).

Remarkable Specimens

The specimen shown at right, located on private land near Grass Valley, California, currently holds both diameter and height records. It is 176.8 cm dbh, 41.1 m tall, with a 30.7 m average crown diameter. Dr. Robert Van Pelt, who measured and photographed this tree, asserts that it is the tallest specimen ever reliably measured; he notes "I do not believe the 48.8 m old American Forests record, which was measured using the Tangent method - with a tree regularly 30 m wide or more, can easily be 15 m off or more" (Van Pelt e-mail 2020.08.02) There are some other big trees. The former official champion was 162.5 cm dbh and 38.40 m tall with a crown spread of 26.21 meters, and grows in Kern County, CA (American Forests 2005). Past champions have ranged up to 180.3 cm diameter (Callahan 2009). In 1998 I found a tree on the the Nacimento-Ferguson road in the southern Santa Lucia Mountains that was 156 cm in diameter, 37 m in height, with a crown spread of 25.1 m. It's noteworthy that these exceptional trees are widely distributed within the species' range.

Ethnobotany

The seeds were an important food source for many Indian groups in California (Kral 1993). The soft, lightweight wood is not durable and is used primarily as firewood (Little 1980).

Observations

Seen widely throughout its range. It can be seen in many California State Parks around the Central Valley and in Yosemite National Park, although it is strangely absent in the vicinity of Sequoia and Kings Canyon National Parks. Within the proper habitat it is abundant and well-developed groves are common.

Remarks

This species was first discovered to botany by David Douglas in 1826, in the Umpqua country in Oregon, near the uttermost northern range limits of the species. Alas, he lost his specimens in crossing the Santiam River, and did not encounter the tree again until February 1831, during a trip to the summit of the Gabilan Range near Monterey, California (Harvey 1948).

The large, heavy cones resemble footballs covered with wooden spikes. It is best to avoid the pine groves on windy days.

John Muir, as always, waxed poetic when he described this tree in the first chapter of My First Summer in the Sierra: "This day has been as hot and dusty as the first, leading over gently sloping brown hills, with mostly the same vegetation, excepting the strange-looking Sabine pine (Pinus Sabiniana), which here forms small groves or is scattered among the blue oaks. The trunk divides at a height of fifteen or twenty feet into two or more stems, outleaning or nearly upright, with many straggling branches and long gray needles, casting but little shade. In general appearance this tree looks more like a palm than a pine. The cones are about six or seven inches long, about five in diameter, very heavy, and last long after they fall, so that the ground beneath the trees is covered with them. They make fine resiny, light-giving camp-fires, next to ears of Indian corn the most beautiful fuel I've ever seen. The nuts, the Don tells me, are gathered in large quantities by the Digger Indians for food. They are about as large and hard-shelled as hazelnuts, --food and fire fit for the gods from the same fruit."

This species is the principal host for the dwarf mistletoe Arceuthobium occidentale (Hawksworth and Wiens 1996).

Citations

American Forests 2005. The 2005 National Register of Big Trees. Washington, DC: American Forests.

Barbour, Michael G. 1988. California upland forests and woodlands. P. 131-164 in Barbour, M.G. and W.D. Billings (eds.), "North American terrestrial vegetation." Cambridge: Cambridge University Press.

Callahan, Frank. 2009. Discovering Gray Pine (Pinus sabiniana) in Oregon. Kalmiopsis 16:1-14. Available: www.npsoregon.org/kalmiopsis/kalmiopsis04.html, accessed 2009.11.14. Useful summary of subjects such as history, ecology, and ethnobotany.

Harvey, A. G. 1948. Douglas of the Fir. Cambridge, Massachusetts: Harvard University Press.

Hunter, Melvin. 1991. Racist Relics: An Ugly Blight On Our Botanical Nomenclature. The Scientist 5[23]:0. http://www.the-scientist.com/yr1991/nov/opin_911125.html, accessed 2004.03.02, now defunct.