​Fire Dendrochronology and Chronology

​Fire Dendrochronology and Chronology

Welcome to the CSU Ä¢¹½ÊÓƵ Museum of Anthropology's exhibit, Fire Without Fear. We are often taught that forest and wildfires are bad, and that suppressing all fires keeps us safe. However, Indigenous peoples of California embrace fire, and intentionally burn to mitigate wildfire spread, and to enhance critical resources and habitats.

Archaeologists, historical ecologists, and geographers use multiple sources of evidence to learn about the characteristics of historical fire geography. One key source of evidence is found in trees. Lower intensity fires do not kill trees, but they may scar them, producing a chronology of fire occurrence and frequency. They study of this tree-based chronology is called Dendrochronology.

Through dendrochronology, scientists have found that fire was much more widespread and frequent before colonization, and that the fire suppression policies enacted by the State of California have drastically reduced fire occurrence, producing major ecological and social challenges.
Read More about Tree Rings, Dates, and Dendrochronology

Tree Rings, Dates, and Dendrochronology

Every year, a tree adds a new layer of growth, forming a visible ring in its trunk. These rings change in thickness depending on the climate—wide rings grow in wet, favorable years, and thin rings form in dry or difficult years. By counting and comparing these rings across many trees, scientists can create long, continuous timelines of past environmental conditions.

Dendrochronology is the science of using tree rings to determine the age of wood and to study past climates. It allows researchers to date wooden objects with remarkable accuracy and to understand how temperature, rainfall, fires, and other natural events shaped the landscape over hundreds or even thousands of years.