Skip to main content
U.S. flag

An official website of the United States government

Scattered tree death contributes to substantial forest loss in California

January 20, 2024

In recent years, large-scale tree mortality events linked to global change have occurred around the world. Current forest monitoring methods are crucial for identifying mortality hotspots, but systematic assessments of isolated or scattered dead trees over large areas are needed to reduce uncertainty on the actual extent of tree mortality. Here, we mapped individual dead trees in California using sub-meter resolution aerial photographs from 2020 and deep learning-based dead tree detection. We identified 91.4 million dead trees over 27.8 million hectares of vegetated areas (16.7-24.7% underestimation bias when compared to field data). Among these, a total of 19.5 million dead trees appeared isolated, and 60% of all dead trees occurred in small groups ( ≤ 3 dead trees within a 30 × 30 m grid), which is largely undetected by other state-level monitoring methods. The widespread mortality of individual trees impacts the carbon budget and sequestration capacity of California forests and can be considered a threat to forest health and a fuel source for future wildfires.

Publication Year 2024
Title Scattered tree death contributes to substantial forest loss in California
DOI 10.1038/s41467-024-44991-z
Authors Yang Cheng, Stefan Oehmcke, Martin Brandt, Lisa Micaela Rosenthal, Adrian Das, Anton Vrieling, Sassan Saatchi, Fabien Wagner, Maurice Mugabowindekwe, Wim Verbruggen, Claus Beier, Stephanie Horion
Publication Type Article
Publication Subtype Journal Article
Series Title Nature Communications
Index ID 70251280
Record Source USGS Publications Warehouse
USGS Organization Western Ecological Research Center