Boreal forest age map shows most trees are still mature and storing carbon despite fires in Canada and Siberia

A new study published in Conservation Biology has produced the first pan-Arctic map of boreal forest age, revealing that most of the biome remains mature despite increasing fires and logging in Canada and Siberia. Researchers used satellite imagery, forest records, and machine learning to estimate that the average boreal forest is 112 years old. Mature stands dominate the far north, while younger forests are concentrated in western Canada and parts of Siberia where disturbance has been frequent. The map gives a clearer picture of where carbon storage is concentrated and where it is at risk. Older forests hold far more carbon than young regrowth, even though young trees grow faster. The study found that old growth persists near lakes, rivers, and in areas with lower fire risk. The authors argue that conservation should target both old stands for their carbon stocks and a mix of ages for resilience. For carbon markets and climate policy, this kind of age mapping matters because it shows where carbon is actually stored and where disturbance is eroding that storage. The full paper is in Conservation Biology and available via PubMed.