The foxtail pine (Pinus balfouriana) is a rare pine that is primarily found in California, United States, where it is found in two areas with a separate subspecies in each, the typical subspecies balfouriana in the Klamath Mountains, and subspecies austrina in the southern Sierra Nevada.A small outlying population exists in southern Oregon, just north of the California border.
The foxtail pine is a tree to 10–20 m (33–66 ft) tall, exceptionally 35 m (115 ft), and up to 2 m (7 ft) in trunk diameter. Its leaves are needle-like, in bundles of five (or sometimes four, in the southern Sierra) with a semi-persistent basal sheath, and 2–4 cm (0.8–1.6 in) long, deep glossy green on the outer face, and white on the inner faces; they persist for 10–15 years. The cones are 6–11 cm (2 3⁄8 - 4 5⁄16 in) long, dark purple ripening red-brown, with soft, flexible scales each with a one millimetre central prickle.
Foxtail pine occurs in the subalpine forest at an elevation of 1,950–2,750 m (6,400–9,020 ft) in the Klamath Mountains, and at 2,300–3,500 m (7,500–11,500 ft) in the Sierra Nevada. In the Sierra Nevada, Foxtail pines are limited to the area around Sequoia and Kings Canyon National Parks. In both areas, it is often a tree line species.
It is thought that Foxtail Pines can live up to 3000 years in the Sierra Nevada, although the highest currently proven age is 2110 years. In the Klamath Mountains, ages are only known to about 1000 years.
Related species 
The Foxtail Pine is closely related to the bristlecone pines, being classified in the same subsection Balfourianae; it has been hybridised with the Great Basin Bristlecone Pine in cultivation, though no hybrids have ever been found in the wild.
- Moore, Gerry; Kershner, Bruce; Craig Tufts; Daniel Mathews; Gil Nelson; Spellenberg, Richard; Thieret, John W.; Terry Purinton; Block, Andrew (2008). National Wildlife Federation Field Guide to Trees of North America. New York: Sterling. p. 83. ISBN 1-4027-3875-7.
- Lanner, RM (2007). The Bristlecone Book. Mountain Press. p. 14. ISBN 978-0878425389.
- Conifer Specialist Group (1998). Pinus balfouriana. 2006. IUCN Red List of Threatened Species. IUCN 2006. www.iucnredlist.org. Retrieved on 11 May 2006.
- Bailey, D. K. 1970. Phytogeography and taxonomy of Pinus subsection Balfourianae. Ann. Missouri Bot. Gard. 57: 210–249.
- Mastrogiuseppe, R. J. & Mastrogiuseppe, J. D. 1980. A study of Pinus balfouriana Grev. & Balf. (Pinaceae). Systematic Botany 5: 86–104.
- Richardson, D. M. (ed.). 1998. Ecology and Biogeography of Pinus. Cambridge University Press, Cambridge. 530 p. ISBN 0-521-55176-5.
Further reading 
- Chase, J. Smeaton (1911). Cone-bearing Trees of the California Mountains. Chicago: A. C. McClurg & Co. p. 99. LCCN 11004975. OCLC 3477527. LCC QK495.C75 C4, with illustrations by Carl Eytel - Kurut, Gary F. (2009), "Carl Eytel: Southern California Desert Artist", California State Library Foundation, Bulletin No. 95, pp. 17-20 retrieved Nov. 13, 2011, Lanner, R.M. 2007 The Bristlecone Book, Ronald M Lanner, Mountain Press 2007 p.14
|Wikimedia Commons has media related to: Pinus balfouriana|
- Arboretum de Villardebelle Photos of cones
- Gymnosperm Database - Pinus balfouriana
- USFS FEIS Introduction to Foxtail pines
- USDA Plants Profile CA Map:
- High Elevation White Pine Educational Website: Pinus balfouriana
- Foxtail Pines in Northwest California