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• High variability in aspen stands makes fire activity in aspen difficult to predict. • Pure stands with herbaceous understories are more likely to reduce fire behavior. • Aspen can burn easily and intensely in windy, dry, or certain seasonal conditions. • Specific management guidelines for aspen fire risk reduction treatments are needed.

Patterns of reburn severity varied by vegetation type, with ponderosa pine-dominated and aspen mixed conifer ecosystems experiencing lower fire severity in reburns and shrublands and pinyon-juniper-oak ecosystems more likely to burn at the same severity in subsequent fires.

The Sentinel-2 constellation of Earth-observing satellites provides similar or even improved estimates of burn severity compared to Landsat 8, further validating its use for mapping fire effects across a diversity of forested ecosystems.