Radiocarbon dating burnt wood
During the late 1950s, several scientists (notably the Dutchman Hessel de Vries) were able to confirm the discrepancy between radiocarbon ages and calendar ages through results gathered from radiocarbon dating tree rings dated through dendrochronology.Today, tree rings are still used to calibrate radiocarbon determinations.
Overall, the C-14 dates from the destruction of the Bronze Age city of Jericho range from as high as 1883 BC to as low as 1262 BC—a range of over 600 years. “Introduction: Radiocarbon dating and the Iron Age of the Southern Levant: Problems and potentials for the Oxford conference,” in The Bible and Radiocarbon Dating: Archaeology, Text and Science. and Bronk Ramsey, C., “C14 Dates and the Iron Age chronology of Israel: a response,” Radiocarbon, 50(2), 2008: 159-180).When the Bronze Age city of Jericho was destroyed by a fire, the burned grain and wood was carbonized, preserving some of it in the destruction layer (Kenyon, Kathleen. This destruction layer, and various bits of charred grain and wood was excavated by archaeologists and sent to laboratories to establish a C-14 date. A New Look at the Archaeological Evidence,” BAR 16:2 (1990): 44-58, 53).The date of the destruction of the final Bronze Age city of Jericho has been a subject of controversy over the last 100 years, and unfortunately the C-14 samples have not settled that controversy. This carbon-14 sample taken at Jericho had been analyzed by the laboratory at the British Museum for the publications of the excavations under Kathleen Kenyon, and the laboratory initially found a date of 1410 BC /- 40 (Kenyon, K, and Holland, TA. London: British School of Archaeology at Jerusalem, 1983, 763). Another C-14 sample from this same destruction layer at Jericho gave results of 3300 /- 7 BP, which calibrates to approximately 1618-1530 BC (Bruins, HJ and van der Plicht, J.Grain samples should be much more reliable in terms of their harvest date, but as one can see from the Jericho samples, the ranges given are not nearly specific enough to settle a debate between a destruction layer dated to either 1550 BC or 1400 BC.
Instead, ceramic typology and various forms of epigraphic evidence should be the primary methods of dating a particular layer of a site from the Bronze or Iron Ages, which is the norm in the archaeology of ancient Israel.
One can count the rings with the core, and that is most common.