Wildfire field guide
Torching vs Crowning: what is the difference?
A tree crown igniting is not automatically the same as a crown fire. Torching usually involves one tree or a small group; crowning describes sustained fire spread through elevated canopy fuels.
Core distinction
Individual crowns vs sustained canopy spread.
NWCG defines torching as the foliage of a single tree or small group of trees burning from the bottom up. Crowning refers to fire advancing through the crowns of trees or shrubs.
Surface fire or ladder fuels ignite individual crowns. The crown involvement is localized and does not necessarily sustain itself across the canopy.
Fire advances from crown to crown. Depending on the type, the crown phase may remain linked to the surface fire or become more independent.
Passive crown fire
Torching fits within passive crown behavior.
NWCG describes passive crown fire as trees or groups of trees torching after ignition by the passing surface fire. Those torching trees can reinforce spread, but the fire remains fundamentally tied to the surface phase.
Active and independent
When canopy spread becomes sustained.
- Active crown fire: a solid flame develops in the crowns while surface and crown phases advance as a linked unit.
- Independent crown fire: fire advances through the crowns without needing energy from the surface fire to sustain combustion and movement.
- Passive crown fire: individual trees or small groups torch, but the canopy phase is not continuously sustained.
Why it matters
The words imply different fire behavior.
Operational reports use these terms to distinguish localized canopy involvement from sustained crown spread. Mislabeling torching as crowning can exaggerate what was observed; calling sustained canopy spread mere torching can understate it.
Sources
NWCG terminology.
NWCG — Independent crown fire ↗
Published 21 September 2026.