Published online by Cambridge University Press: 20 January 2017
Radiocarbon dating is a useful tool in archaeological research, but the precision hoped for by some is not attainable because of the nature of the radiocarbon assay itself, possible contaminations, the Suess effect, and especially the peculiar nature of wood structure and growth. Wood and charcoal, unlike animal remnants, will not necessarily give the age corresponding to the time when the tree died or was cut; they will give only the age of the particular fragment used in the radiocarbon assay. If wood comes from the central portion of a large tree stem, there may even be several hundred years difference between its radiocarbon date and the date of the corresponding archaeological level. Such discrepancies are common in the recent finds at Teotihuacάn. Even the apparently erroneous date of 1474 ± 230 B.C. for Teotihuacάn can thus be explained. Other radiocarbon dates should also be evaluated with this in mind.
Contribution No. 331 of the Botany Department, Pennsylvania State University.