Pinus Longaeva

Distribution of Pinus Longaeva in the United States

Pinus Longaeva, also known by its common name the “Great Basin Bristlecone Pine” and “Intermountain Bristlecone Pine,” are part of the family Pinaceae. They grow to be around 16 m tall and are quite variable to their morphology. Those trees who grow at lower elevation tend grow tall and upright. This is in contrast to those who grow at higher elevation whose morphology are more twisted and contorted. Pinus Longaeva tend to have a relatively thin bark. This makes them more susceptible to severe fires. They occasionally form a krummholz at the alpine timberline. Their leaves survive a remarkably long time, persisting around 10 – 43 years, and are upcurved. The maturation for a seed cone of Pinus Longaeva is approximately two years.

Pinus Longaeva are found in only a relatively few states; California, Nevada and Utah to be exact. The best places to observe these conifers are in the Bryce Canyon National Park and Cedar Breaks National Monument (Utah), Inyo National Forest of California and the Great Basin National Park (Nevada). Remarkably they can grow at high elevations, anywhere from 1700 meters to 3400 meters. Pinus Longaeva is highly drought tolerant. They maximize their water absorption by having roots that are shallow and are highly branched. According to Gymnosperm Database, Pinus Longaeva’s lower timberline is “defined by its tolerance of heat and drought,” and it’s upper limits are limited by the cold winter temperature beyond which it cannot grow.

Pinus Longaeva are among the longest living trees in the world. Actually, the oldest living tree that is known is nicknamed “Methuselah” which is over 4700 years old.

It seems likely that individual trees may exist that are older than 5,000 years old. The identification of these trees however, may never be possible. This is due to the fact that the pine has an ability to adopt a strip-bark morphology. Trees with this morphology have a lining of living cambium that is found on the leeward side of the trunk. Wood that is exposed will take the brunt of the ice crystals and sand that is blown towards the tree.

This will eventually wear away the wood that is exposed and the tree rings that were present will now be destroyed.

Pinus Longaeva also has been used in what is called dendroclimatic reconstruction. This is possible because dead wood decays very slowly. The arid and cold habitat which Pinus Longaeva occupies also contribute to the slow decay of dead wood. Some samples of dead wood have been found that have been dated over 10,000 years ago.

John Huntinghouse, Fall 2007