The study of tree rings is called dendrochronology. Dendrochronology is the scientific method of dating tree rings and using the patterns of tree rings to establish a timeline. It is based on the fact that trees produce new growth rings each year, and the width and density of these rings can be influenced by environmental conditions such as temperature, precipitation, and sunlight. By studying tree rings, dendrochronologists can determine the age of trees and reconstruct past climate and environmental conditions. Dendrochronology has been used to study a wide range of topics, including climate change, forest ecology, and human history.