Text and photos by Heather Cline 

Ancient Bristlecone pine trees are special species of tree for many reasons, including their age, growth rate, ability to withstand tough conditions, and their unique appearance. These trees live exclusively at high elevations, between 5,600 and 11,200 feet where winters are cold and harsh, and summers are sunny and windy.

There are two species under the Bristlecones: the Great Basin bristlecone pine and the Colorado bristlecone pine. The Great Basin bristlecone is found in California, Nevada, and Utah, while the Colorado bristlecone is found in Arizona and New Mexico with the Great Basin bristlecone being the longer-lived of the two species.

Growth:

• The bristlecone pine is the world's slowest-growing tree with about one inch of growth every hundred years. Its slow and steady growth can be attributed to the tough conditions it lives in, from freezing temperatures to dry soils, and high winds. This slow growth rate also acts as a defense mechanism making the wood dense and heavy, helping to guard against insects, fungi, rot, and weathering.
• Bristlecone pines range from about 15 to 50 feet tall.
• Bristlecones rely on a single tap root and utilize shallow roots to chase cracks in soil to pull in water and send nutrients through the tree. They can slowly start to shut off flow to outer limbs and hold on to the most viable living tissue, for hundreds of years. This is partly why they have this unique and twisted shape. The bristlecone’s clusters of needles can remain on the tree for 40 years, a significant length compared to the average 2-3 years for other pines.

Age:

• Probably the most well known feature of these trees are their age. They are the oldest in the world, some exceeding 5,000 years. They are sometimes referred to as living fossils because they are one of the few species of trees that have remained unchanged for millions of years.
• The oldest verified tree was named Prometheus and was located in the Wheeler Peak area of Great Basin National Park, but was inadvertently cut down by a researcher and forest service personnel in 1964 when his survey tool got stuck in the tree and was granted permission to cut it down to retrieve it. At that time, the tree was verified to be 4,862 years old.
• Since that time, another tree was discovered in the White Mountains of California and named Methuselah, estimated to be about 4,850 years old. At the time it was found, it was thought to be the oldest living Bristlecone but in 2012, another discovery of a nearby tree was estimated to be more than 5,060 years old and now holds the honor of oldest living tree.

Features and Characteristics:

• The Ancient Bristlecone typically grows twisted branches with bark that is orange-yellow to light brown. These trees may look dead to some with trunks that lack any bark but tiny sprigs of green plumes are an indicator of its status. Even if there is just a small cluster, the tree is alive and growing.
• Like most coniferous trees, the bristlecone produces pinecones. The female cones have spikes that are tipped with bristles and this is where this tree gets it name. The cones are small and only grow about an inch long. The growing cones have a deep purple hue, which is useful for absorbing the sun's heat, while the mature cones turn brown in color after two years.
• Bristlecone pine trees have very long, slender needles that are dark green in color, and can grow up to 18 inches long. The needles occur in clusters of five and grow in pairs along the branches.

Ecological Significance:

• Bristlecone pines are significant to the ecosystem because they provide food and shelter for wildlife and help to control erosion. They are also a keystone species, meaning their presence has a significant impact on their environment
• Despite the hardiness they have developed to survive in arid climates and high elevations, they are vulnerable to changing climate conditions, particularly drought. Several populations of Great Basin bristlecone pines experienced a rare die-off event in 2022 that resulted from a combination of drought stress and bark beetle infestation.

I hope you enjoyed this post. To see more of my Ancient Bristlecones images, check out the gallery here.