World Library  
Flag as Inappropriate
Email this Article

Bristlecone pine

Bristlecone Pine
A Great Basin Bristlecone Pine grove
The eponymous bristles
Scientific classification
Kingdom: Plantae
Division: Pinophyta
Class: Pinopsida
Order: Pinales
Family: Pinaceae
Genus: Pinus
Subgenus: Ducampopinus
Section: Parrya
Subsection: Balfourianae

Pinus aristata
Pinus longaeva
Pinus balfouriana

A bristlecone pine can refer to one of three species of pine trees (family Pinaceae, genus Pinus, subsection Balfourianae). All three species are long-lived and highly resilient to harsh weather and bad soils. One of the three species, Pinus longaeva, is the longest-lived life form on Earth; the oldest individual is more than 5,000 years old,[1] making it the oldest known individual of any species.

Despite their potential age and low reproductive rate, bristlecone pines, particularly Pinus longaeva, are usually a first succession species, tending to occupy new open ground.[2] They generally compete poorly in less-than-harsh environments, making them hard to cultivate.[2] In gardens, they succumb quickly to root rot.[3] They do very well, however, where most other plants cannot even grow, such as in rocky dolomitic soils in areas with virtually no rainfall.[2]

Bristlecone pine grow in scattered subalpine groves at high altitude in arid regions of the Western United States. The name comes from the prickles on the female cones.[4]


  • Species and range 1
  • Description 2
  • Oldest living organisms 3
  • See also 4
  • References 5
  • External links 6

Species and range

There are three closely related species of bristlecone pines:

  • Rocky Mountains bristlecone pine Pinus aristata in Colorado, New Mexico and Arizona. The most populous species; capable of forming closed canopies and, unlike the other two, is commonly cultivated.
  • Foxtail pine Pinus balfouriana with two disjunct populations found in the Klamath Mountains (subspecies balfouriana) and the southern Sierra Nevada[5] (subspecies austrina). A small outlying population was reported in southern Oregon, but was proven to have been misidentified.[6] Forms the thickest groves of the three.

At least some of the three species can hybridize in cultivation, but the ranges of wild populations do not overlap. The Colorado River and Green River produces a 160-mile (260 km) gap between the ranges of P. longaeva and P. aristata and the northern Owens Valley provides a 20-mile (30 km) gap between the ranges of P. longaeva and P. balfouriana.[7]


Bristlecone pines grow in isolated groves just below the tree line, between 5,600 and 11,200 ft (1,700 and 3,400 m) elevation on dolomitic soils.[4] The trees grow in soils that are shallow lithosols, usually derived from dolomite and sometimes limestone, and occasionally sandstone or quartzite soils. Dolomite soils are alkaline, high in calcium and magnesium, and low in phosphorus. Those factors tend to exclude other plant species, allowing bristlecones to thrive.[8] Because of cold temperatures, dry soils, high winds, and short growing seasons, the trees grow very slowly. Even the tree's needles, which grow in bunches of five, can remain on the tree for forty years, which gives the tree's terminal branches the unique appearance of a long bottle brush.

Gnarled bristlecone pine wood

The bristlecone pine's root system is mostly composed of highly branched, shallow roots, while a few large, branching roots provide structural support. The bristlecone pine is extremely drought tolerant due to its branched shallow root system, its waxy needles, and thick needle cuticles that aid in water retention.[7]

The wood is very dense and resinous, and thus resistant to invasion by insects, fungi, and other potential pests. The tree's longevity is due in part to the wood's extreme durability. While other species of trees that grow nearby suffer rot, bare bristlecone pines can endure, even after death, often still standing on their roots, for many centuries. Rather than rot, exposed wood, on living and dead trees, erodes like stone due to wind, rain, and freezing, which creates unusual forms and shapes.

The bristlecone pine has an intrinsically low rate of reproduction and regeneration, and it is thought that under present climatic and environmental conditions the rate of regeneration may be insufficient to sustain its population.[9] The species are on the International Union for Conservation of Nature (IUCN) red list.[9] The species are labeled under Least Concern (LC). The justification for this being that no subpopulations for Great Basin bristlecone pines are decreasing. Subpopulations seem to be increasing or remaining stable.[9] Many bristlecone pine habitats have been protected, including the Inyo National Forest's Ancient Bristlecone Pine Forest in the White Mountains of California and the Great Basin National Park in Nevada,[10][11] where cutting or gathering wood is prohibited.[10]

A Great Basin bristlecone pine overlooks Bryce Canyon National Park, June 2013.

The green pine needles give the twisted branches a bottle-brush appearance. The needles of the tree surround the branch an extent of about one foot near the tip of the limb.[12] The name bristlecone pine refers to the dark purple female cones that bear incurved prickles on their surface.[4][11] The dark color of these cones help to absorb heat. After maturity, which takes about two years, the cones will become brown in color.[12] These ancient trees have a gnarled and stunted appearance, especially those found at high altitudes,[7] and have reddish-brown bark with deep fissures.[13] As the tree ages, much of its vascular cambium layer may die. In very old specimens, often only a narrow strip of living tissue connects the roots to a handful of live branches. Even though the trees needles may age, they still remain functional in regulating water and by their ability to photosynthesize.[7]

Oldest living organisms

This one might have died hundreds of years ago, but still stands. Its wood gives clues to scientists who read the rings to compare to rings of living trees, making a 9,000-year-long record.

Bristlecone pines are known for attaining great ages. A specimen of Pinus longaeva located in the White Mountains of California is 5,065 years old according to measurements by Tom Harlan.[1] This is the oldest known individual tree in the world. The identity of the specimen is being kept secret by Harlan. Another well-known bristlecone from the White Mountains is Methuselah which is 4,847 years old. Its specific location is also being kept secret.[14]

The other two species, Pinus balfouriana and Pinus aristata are also long-lived, though not to the extreme extent of P. longaeva; specimens of both have been measured or estimated to be up to 3,000 years old.[15] It is believed that the longevity of the trees is related to the proportion of dead wood to live wood. This high ratio reduces respiration and water loss, thereby extending the life of the tree.[9]

Note that trees that reproduce via cloning can be considered to be much older than bristlecone pines. A colony of 47,000 quaking aspen trees (nicknamed "Pando"), covering 106 acres (43 ha) in the Fishlake National Forest of the United States, has been estimated to be 80,000 years old, although tree ring samples date individual, above-ground, trees at only an average of about 130 years.[16][17]

The bristlecone pine is invaluable to dendroclimatologists, because it provides the longest continual climatically sensitive tree-ring chronologies on the planet. By cross-dating millennia-old bristlecone pine debris, some chronologies reach beyond 9,000 years before present.[7] In addition, ratios of stable carbon isotopes from bristlecone pine tree rings are sensitive to past variations in moisture availability. This information can be used to reconstruct precipitation changes in the past.[18]

The Rocky Mountain population is severely threatened by an introduced fungal disease known as white pine blister rust, and by pine beetles.[19] Another problem that the species face is climate change as temperatures have increased 0.5–1 °C within the past 30 years throughout the southern Rocky Mountain range. These changes in climate would mostly affect trees in higher elevations. With these problems, the genetic diversity within the species has become a concern.[20]

See also

  • List of long-living organisms


This article incorporates text from the ARKive fact-file "Bristlecone pine" under the and the .

  1. ^ a b "Oldlist". Rocky Mountain Tree Ring Research. Retrieved 2013-01-08. 
  2. ^ a b c Howard, JL (2004). "Pinus longaeva". Fire Effects Information System. USDA. Retrieved 2008-12-02. 
  3. ^ EOL
  4. ^ a b c Bristlecone pine media at ARKive
  5. ^ Moore, Gerry; Kershner, Bruce; Tufts, Craig; Mathews, Daniel; et al. (2008). National Wildlife Federation Field Guide to Trees of North America. New York: Sterling. p. 83.  
  6. ^ Kauffmann, Michael E. (2012). Conifer Country. Kneeland, CA: Backcountry Press.  
  7. ^ a b c d e Fryer, Janet L (2004). "Pinus longaeva". U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory. 
  8. ^ Coop, JD; Schoettle, AW (2009). "Regeneration of rocky mountain bristlecone pine (pinus aristata) and limber pine (pinus flexilis) three decades after stand-replacing fires". Forest Ecology and Management 257 (3): 893–903.  
  9. ^ a b c d Stritch, L; Mahalovich, M; Nelson, KG. "Pinus longaeva". IUCN Red List.  
  10. ^ a b "Global Trees Campaign". March 2008. Retrieved 30 July 2011. 
  11. ^ a b "The Ancient Bristlecone Pine". August 2003. Retrieved 30 July 2011. 
  12. ^ a b "Bristlecone pines". U.S. National Park Service. 
  13. ^ "The Gymnosperm Database". March 2008. Retrieved 30 July 2011. 
  14. ^ Kinkead, Gwen (June 17, 2003). "At Age 4,600-Plus, Methuselah Pine Tree Begets New Offspring". New York Times. 
  15. ^ Bain, G. Donald (2001). "Explore the Methuselah Grove". NOVA Online: Methuselah Tree. PBS. 
  16. ^ Grant, Michael C. (1 October 1993). "The Trembling Giant". Discover Magazine. Retrieved 8 May 2008. 
  17. ^ "Quaking Aspen".  
  18. ^ Bale, RJ; Robertson, I; Salzer, MW; Loader, NJ; et al. (2011). "An annually resolved bristlecone pine carbon isotope chronology for the last millennium". Quaternary Research 76 (1): 22–29.  
  19. ^ Robbins, Jim (2010-09-27). "Old Trees May Soon Meet Their Match". The New York Times. 
  20. ^ Schoettle, AW; Goodrich, BA; Hipkins, V; Richards, C; Kray, J (2012). "Geographic patterns of genetic variation and population structure in pinus aristata, rocky mountain bristlecone pine". Canadian Journal of Forest Research 42 (1): 23–37.  
  • Bailey, D.K. (1970). "Phytogeography and taxonomy of Pinus subsection Balfourianae". Ann. Missouri Bot. Gard. 57: 210–249. 
  • Richardson, D.M., ed. (1998). Ecology and Biogeography of Pinus. Cambridge: Cambridge University Press.  

External links

  • Arboretum de Villardebelle Images of cones (scroll to bottom of page)
  • Pinus aristataGymnosperm Database -
  • Pinus longaevaGymnosperm Database -
  • Pinus balfourianaGymnosperm Database -
  • Prometheus: The Martyred One
  • OpenRoad.TV (video story about the Ancient Bristlecone Pines)
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.