One for the Ages: Bristlecone Pines Break 4,650-Year Growth Record: Scientific American

Description

Bristlecone pine trees dot the White Mountains in eastern California, giving the stark and rocky landscape one of its few highly visible signs of life. These gnarly-barked trees can survive at altitudes of up to 3,470 meters, although their growth rate at these heights is limited because of cold temperatures. But those limits have been loosening lately. In the past 50 years, as regional temperatures have warmed, the growth of bristlecone pine trees at high altitudes has been accelerating, whereas that of trees lower down the slopes has not, according to the results of a study published November 16 in the Proceedings of the National Academy of Sciences .

The research focused on Great Basin bristlecone pines ( Pinus longaeva ), which grow in six western U.S. states and are among the longest-lived organisms on Earth. Some pines reach ages of up to 5,000 years, which gave the study authors an opportunity to put together a record going back nearly as far that compares bristlecone growth rates at various altitudes.

To arrive at their findings, study lead author Matthew Salzer , a research associate in the Laboratory of Tree-Ring Research at the University of Arizona in Tucson, and his colleagues studied 678 tree ring radii of bristlecone pines, both living and dead, from a site on ...

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