Dating is the classical applications of dendrochronology. Samples are extracted from wood subjects (ship wrecks, foundations, roof constructions, music instruments) and the tree-ring widths are measured. The ring-width patterns are subsequently visually and statistically compared to regional chronologies.
Regional chronologies have been built up from sometimes thousands of ring-width series from trees and woods of the same species originating from a certain area. Many of them are available from the International Tree Ring Data Base (ITRDB).
Chronologies serve for dating and dendroprovenancing. To do so the ring-width series of a wooden object of unknown age is compared to all available chronologies of the wood species. By getting a significant match with one or more chronologies the cutting date of the tree used for the wooden object can be determined. The regional chronology showing the strongest match with the ring-width series moreover indicates the origin of the wood. For detailed information see Working Fields - Dendrochronology.