The annual rings from cross sections of selected tree stems provide a means of dating and reconstructing events of the past. The number of rings, together with anatomical features in the ring structure, have been used widely to estimate the minimum date of such occurrences as recent glacial advances or retreats, lake level fluctuations, landslides, floods, fires, and many other types of natural or man‐made changes. Also, the precise cross dating of ‘drought‐sensitive,’ tree‐ring chronologies has been used to establish the cutting date of archaeological timbers, periods of stream downcutting, and occurrences of fires. Rates of slope degradation have been estimated, and radiocarbon dating is being refined and calibrated by dates obtained from analyses of tree rings. There are many additional app