The Laboratory of Tree-Ring Research
Dendrochronology was founded in Arizona by A.E. Douglass during the early 1900s. The Laboratory was approved as a University department on December 4, 1937, and it came into operation on 1st July 1938. The Arizona Board of Regents established the Laboratory “to promote teaching and research in dendrochronology”, and it is the oldest, largest and most comprehensive dendrochronology program in the world.