Back dating tools
The 1906 ring pattern in wood Sample A (which was cut from Stump A) correlates with a 1906 ring pattern in Sample B which was cut from an older, undated Stump B. By matching up similar spaced rings in Samples B, C and D, the ages of ancient timbers can be determined.As long as the wood samples being compared have some ring patterns that coincide, time may be extended back through an unbroken succession of growth rings.But since the year 2000 or so, older artifacts have pushed the date of settlement back to between 13,000 and 16,000 years.The new finds, made in the Gault Site in Central Texas, might trace their roots even further back.
A tree was felled in 1982 giving rise to Stump A which dates back to 1906.
The rings are very close together and require magnification in order to count them.
Due to the enormous size of the trunk, it was necessary to extrapolate the age based on the radius of the trunk.
In this example, wood Sample D dates back to the year 1691.
This represents an unbroken succession of 291 annual rings, almost three centuries of time recorded in four small pieces of wood.