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World's oldest tree was cut down "by mistake" |
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Written by Staff Writer
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Sep 25, 2007 at 02:22 PM |
The Bristlecone Pine (Pinus longaeva) was first identified as a long-lived tree by Dr Edmund Schulman following surveys in California's White Mountains in 1954. The oldest pines grow at elevations above 3,000 metres in arid, rocky areas of the Great Basin that covers the state of Nevada and parts of Utah and California. (This mountainous area of 500,000 square kilometres has no rivers or creeks flowing out of it.) They exist on the tree line in severe conditions, and often appear to be mostly dead, with only part of the trunk having living bark and leaves. This growth strategy is a response to damage from climate and lightning strikes, and allows the tree to exist on limited resources.
The bristlecones of Wheeler Peak in Nevada were believed to be older than those found in California. In 1964 a geology student called Donald R. Currey came to Wheeler Peak to study ice age glaciers, partly by collecting tree ring data. Using coring tools, he identified trees over 4,000 years old.
When his coring tool jammed inside a massive tree, he asked for, and received, permission from the US Forest Service to cut the tree off at 2.4 metres above the ground and keep a horizontal slab for study. When this slab had its rings counted, it turned out to be over 4,844 years old. Later cores taken closer to ground level by dendrochronologist Don Graybill showed it to be 4,862 years old - the oldest living thing ever discovered.
Wheeler Peak is now part of the Great Basin National Park, which was created in 1986.
The oldest tree now living is a 4,600+ year old bristlecone called "Methuselah" in the White Mountains of California. Some reports have it as 4,789 years old.
distribution map Until 1970 bristlecones were regarded as a single species. Then D.K. Bailey demonstrated that there were differences in the structure of the needles and cones between the bristlecones of California, Nevada and Utah from those of Arizona, Colorado and New Mexico, sufficient to warrant splitting them into two species : Pinus longaeva and P. aristata .
The Bristlecone Pine is a specialist not only at surviving the harsh climate, but also at coping with dolomitic soils that are alkaline and low in nutrients. With only three summer months each year, and less than 25 cm of rainfall, the bristlecone pines often only add a quarter of a millimetre to their girth each year.
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