DENDRA Dendrochronologia
Section 47 · a Sierra pine · felled 2023

A tree's whole life, read one ring a year.

This disc grows outward from the pith exactly as the tree did — a broad ring for a wet year, a hair for drought, a black scar where fire came through. Move across it to read any season back to 1840.

Section 47 · 1840–2023
Move across the rings — or use ← → keys — to read a year.

Every ring is a sentence the season wrote itself.

01

How a ring forms

Each spring the cambium — a single living layer under the bark — lays down large, thin-walled cells that move water fast. That is the pale earlywood.

By late summer growth slows; cells turn small and dense. That dark band is the latewood, and its edge is the line you count.

02

Reading the weather

Width is memory. A wet, warm year opens a broad ring; a drought closes it to a fraction of a millimetre. Match those widths against known climate and a ring becomes a date.

Cross-dating overlapping cores lets a chronology run back thousands of years — long past any single tree.

03

The scars

Fire kills the cambium on one side; the tree walls off the wound and grows around it, leaving a char lens you can date to the year and, from the char height, even the season.

This specimen carries three: 1868, 1911, and the 1988 crown fire it barely survived.