Tree ring dating method
This statement by Ferguson may give us a clue: “Occasionally, a sample from a specimen not yet dated is submitted for radiocarbon analysis.
The date obtained indicates the general age of the sample, this gives a clue as to what portion of the master chronology should be scanned, and thus the tree-ring date may be identified more readily.”And, again: “Radiocarbon analysis of a single, small specimen, that contains a 400-year, high quality ring series indicates that the specimen is approximately 9000 years old.
Such a suspicion is not unfounded, for Professor Damon, after assuring us of his personal confidence in tree-ring dates, adds: “Nevertheless, it is reassuring to have some objective comparison, for example, with another method of dating.
This is, in fact, provided by carbon-14 dating of historically dated samples.” If tree-ring dates need to be bolstered by comparison with radiocarbon dates in the range where they are supported by historical dates, back only 4,000 years, what is to be said of the need 4,000 or 5,000 years before that?
In recent years, however, it has been found that the bristlecone pine, an unpretentious, scrubby-looking tree that grows on high, rocky slopes in the southwestern United States sometimes lives even longer.
One tree in Nevada is reported to be 4,900 years old.
By using this correction curve, the radiocarbon dating laboratories have come to rely fully on the accuracy of tree-ring chronology, also called dendrochronology.
Do these admissions give reason to suspect that perhaps the tree-ring chronology is not as well-anchored as it seems to be, but that its proponents look for support to radiocarbon dating?From a uniformitarian point of view, such a statement is reassuring enough. Also, the present-day location of the bristlecone pine groves might then have been at a much lower elevation.But this viewpoint overlooks the abundant evidence that the climate was much more temperate before the Deluge of 2370 B. Both of these differences, in harmony with the opinion quoted, could have resulted in more multiple rings in trees then living.Even more interesting is Ferguson’s comment about the possibility that a tree may produce two or three rings in a single year: “In certain species of conifers, especially those at lower elevations or in southern latitudes, one season’s growth increment may be composed of two or more flushes of growth, each of which may strongly resemble an annual ring.
Such multiple growth rings are extremely rare in bristlecone pine, however, and they are especially infrequent at the elevation and latitude of the sites being studied.” So, under present climatic conditions, multiple rings are rare.After his death in 1958, this work was resumed by Professor C. He claims to have established a tree-ring chronology for the bristlecone pine all the way back to 5522 B. Can there be any reason to doubt that it is correct?