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Prometheus (tree)

The stump (lower left) and some remains of the Prometheustree (center), in the Wheeler Bristlecone Pine Grove at Great Basin National Park near Baker, Nevada

Prometheus (aka WPN-114) was the oldest known non-clonal organism, a Great Basin Bristlecone Pine (Pinus longaeva)tree growing near the tree line on Wheeler Peak in eastern Nevada, United States. The tree, which was at least 4862 yearsold and possibly more than 5000 years, was cut down in 1964 by a graduate student and United States Forest Servicepersonnel for research purposes.[1]

The people involved did not know of its world-record age before the cutting (see below). However, the circumstances and decision-making process leading to the felling of the tree remain controversial; not all of thebasic facts are agreed upon by all involved. The name of the tree refers to the mythological figure Prometheus, who stole firefrom the gods and gave it to man.[2] The designation WPN-114 was given by the original researcher, Donald Rusk Currey,and refers to the 114th tree sampled by him for his research in Nevada’s White Pine County.

About the tree

The grove in which Prometheus grew, withthe headwall of Wheeler Peak in thedistance

Prometheus was a living member of a population of bristlecone pine treesgrowing near the tree line on the lateral moraine of a former glacier onWheeler Peak, in Great Basin National Park, eastern Nevada. Wheeler Peakis the highest mountain in the Snake Range, and the highest mountain entirelywithin the state of Nevada. The bristlecone pine population on this mountain isdivided into at least two distinct sub-populations, one of which is accessible bya popular interpretive trail. Prometheus, however, grew in an area reachableonly by off-trail hiking. In either 1958 or 1961, a group of naturalists whoadmired the grove in which the tree grew gave names to a number of thelargest or most distinctive trees, including Prometheus.[3]


Currey
originally aged the tree at, minimally, 4844 years. A few years later, this was increased to 4862 years by Donald Graybill of theUniversity of Arizona’s Laboratory of Tree-Ring Research. However, these ring counts were done on a trunk cross section taken about2.5 m (8 feet) above the original germination point of the tree, because the innermost rings were missing below that point. AdjustingGraybill’s figure of 4862 by adding in the estimated number of years required to reach this height, plus a correction for the estimated numberof missing rings (which are not uncommon in trees growing at the tree line), it is probable that the tree was at least 5000 years old whenfelled. This makes it the oldest unitary (i.e. non-clonal) organism ever discovered, exceeding even the Methuselah tree of the White MountainsSchulman Grove, in California by two to three hundred years.[citation needed]

Whether Prometheus should be considered the oldest organism ever known depends on the definition of “oldest” and “organism”. However, in a clonal organism the individual clonal stems are nowhere near as old, and no part of the organism at any given point in timeis particularly old. Prometheus was thus the
oldest non-clonal organism yet discovered, with its innermost, extant rings exceeding 4862 years of age.

The cutting of the tree

The cut stump of the Prometheus tree

In the 1950s dendrochronologists were making active efforts at finding the oldest living tree species, in order to use the analysis of therings for various research purposes, such as the evaluation of former climates, the dating of archaeological ruins, and addressing the basicscientific question of maximum potential lifespan. Bristlecone pines in the White Mountains of California and elsewhere were discovered byEdward Schulman to be older than any species yet discovered. This spurred interest in finding very old bristlecones, possibly older than theMethuselah tree, aged by Schulman in 1957 at over 4700 years.


Donald
R. Currey was a graduate student at the University of North Carolina at Chapel Hill studying the climate dynamics of the Little Ice Age using dendrochronology techniques. In 1963 he became aware of the bristlecone populations in the Snake Range in general, andon Wheeler Peak in particular. Based on the size, growth rate and growth forms of some of the trees he became convinced that some veryold specimens existed on the mountain, cored some of them, and found trees exceeding 3,000 years old. However, Currey was not able toobtain a continuous series of overlapping cores from WPN-114. Here, stories diverge. It is not clear whether Currey requested, or ForestService personnel suggested, that he cut down and section the tree in lieu of being able to core it. There is also some uncertainty as to whya core sample could not be obtained. One version has it that he broke or lodged his only long increment borer and could not obtain anotherbefore the end of the field season,[5] another claims he broke two of them, while another implies that a core sample was too difficult toobtain and also would not provide as much definitive information as a full cross section of the tree would.[6]

In addition, there are conflicting views over Prometheus being unique in the Wheeler Peak grove. It is reported that Currey and/or the Forest Service personnel who authorized the cuttingbelieved the tree was just one of manylarge, very old trees in the grove. Others, at least one of whom was involved in the decision-making and tree cutting, believe that the tree wasclearly unique — obviously older than other trees in the area. At least one person involved says that Currey knew this to be true at the time, although there is no known admission fromCurrey himself that he knew this, and others have disputed that the tree, based on observation alone, was obviously much older than the others.[3][6]

Another uncertainty is that it is not clear why the felling of such an old tree was necessary given the topic Currey was studying. Since the Little Ice Age started no more than 600 yearsago, many trees could presumably have provided the information he was seeking for that time period. However, in Currey’s original report in the journal Ecology (Currey, 1965) he refers tothe Little Ice Age as encompassing the period from 2000 BC to the present, thus defining the Age over a much longer time period than is currently accepted. Whether this was the commonsentiment at the time is not known. In the article, Currey indicates that he sectioned the tree as much from the question of whether the oldest bristlecones were necessarily confined toCalifornia’s White Mountains (as some dendrochronologists had been claiming) as from its usefulness in regard to studies of the Little Ice Age.[6]

Whatever the rationale, the tree was cut down and sectioned in August 1964, and several pieces of the sections hauled out to be processed and analyzed, first by Currey, then by others inlater years. Sections, or pieces of sections have ended up in various places, some of which are publicly accessible, including the Great Basin National Park visitor center (Baker, Nevada), the Ely Convention Center (Ely, Nevada), the University of Arizona Laboratory of Tree-Ring Research (Tucson, Arizona), and the US Forest Service’s Institute of ForestGenetics (Placerville, California).

Repercussions

It has been argued that the cutting down of Prometheus was an important factor in the movement to protect bristlecones in general, and the Wheeler Peak groves in particular.[7] Therehad been a movement to protect the mountain and contiguous areas in a national park before the incident, and 22 years later the area gained national park status.

See also

Notes

References

  • Radiolab, WNYC, 2010-09-03.
  • Hitch, Charles J. 1982. Dendrochronology and Serendipity. American Scientist 70(3): 300–05.
  • Kelsey, Michael R. 1999. Hiking and Climbing in the Great Basin National Park: A Guide to Nevada’s Wheeler Peak, Mt. Moriah and the Snake Range. Kelsey Publishing, Salt LakeCity, UT. ISBN 0-9605824-8-7. Contains a map showing the approximate location of the tree on Wheeler Peak, as does another of Kelsey’s books, Mountains of the World.
  • Lambert, Darwin. 1991. Great Basin Drama: The Story of a National Park. Roberts-Rinehart Publishers. ISBN 0-911797-95-5
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