- The Laboratory of Tree-Ring Research (LTRR) at the University of Arizona in Tucson is the world's preeminent center for dendrochronology, the scientific study of tree rings - Founded in 1937 by A.E. Douglass, who established the modern science of dendrochronology, the lab is a global leader in reconstructing past environmental, climatic, and social changes using the data stored in tree rings - Scientists use ring width and cell density to analyze centuries of drought and climate variability - Tree rings provide precise dating for wooden artifacts and prehistoric sites, helping to narrow down dates for events like volcanic eruptions - The LTRR houses the world's largest collection of wood research specimens, which serve as an irreplaceable record of life on Earth over the past 100 years - The lab is located in the Bryant Bannister Tree-Ring Building on the University of Arizona campus Map