Brushfire Causes and Prevention: Human and Natural Ignition Sources

Brushfires (wildland fires in shrub/grass) ignite from natural and human causes.

Major Causes

• Unattended campfires: Incomplete extinguishment → smoldering rekindle
• Discarded cigarettes: Glowing embers ignite dry duff
• Equipment use: Mowers, trimmers, chainsaws, vehicles — sparks, hot exhaust
• Power lines: Arcing, conductor slap, transformer failure (high wind)
• Arson: Intentional ignition
• Lightning: Dry thunderstorms (rain evaporates before ground)
• Debris burning: Escaped controlled burns
• Fireworks: Seasonal spike

Prevention (Individual)

• Fully extinguish campfires (drown, stir, feel)
• Dispose cigarettes in water/sand
• Maintain equipment (spark arrestors)
• Observe burn bans/red flag warnings
• Create defensible space around home (zone 0–5 ft: non-combustible)

Community

Fire-adapted communities: codes, evacuation planning, prescribed fire, utility hardening.