Dendrochronology

Dendrochronology, a name derived from the Greek words for “tree” and “knowing the time,” is a set of techniques by which the annual growth layers of trees, called tree annual rings, can be assigned to the specific year of their formation. The history of changes in the tree's environment can be reconstructed using various properties of annual tree rings, for example, their width, cell size, wood density, trace element composition, and radioactive and stable isotope ratios. Andrew Douglass established the scientific basis of dendrochronology in the early years of the 20th century in North America. Douglass, the founder of the Laboratory of Tree-Ring Research at the University of Arizona in Tucson, invented the technique of cross-dating by means of skeleton plots, that is, the process ...