Mariposa County

Summary

• Fire hazard severity zones

  Share of the land in each CAL FIRE hazard class

  Map
  1. Very High 219,135 acres · State Responsibility Area 23%
  2. High 206,223 acres · State Responsibility Area 22%
  3. Moderate 18,301 acres · State Responsibility Area 2%
  4. Not mapped by CAL FIRE 492,619 acres · Mostly federal land 53%

  936,278 acres of land in all, 443,659 of it in the State Responsibility Area. State zones are the ones the State Fire Marshal designated, in effect since April 1, 2024. Local zones are CAL FIRE's 2025 recommendation, which each city or county adopts by ordinance and can make stricter. How to read fire zones

• Fire history

  The 10 largest of 590 fires that burned here

  Map
  1. 2018 Ferguson Fire Cause: Miscellaneous 96,688 acres here
  2. 2017 Detwiler Fire Cause: Miscellaneous 81,819 acres here
  3. 1924 Unnamed fire Cause: Miscellaneous 43,313 acres here
  4. 1987 Larson Fire 48,087 acres in total · Cause: Lightning 39,081 acres here
  5. 1924 Unnamed fire 37,135 acres here
  6. 2008 Telegraph Fire Cause: Miscellaneous 34,079 acres here
  7. 2022 Oak Fire 18,954 acres here
  8. 1990 A-Rock Fire Cause: Lightning 17,758 acres here
  9. 1987 Hamm Fire 33,144 acres in total · Cause: Lightning 16,940 acres here
  10. 1934 Unnamed fire 14,731 acres here

  And 580 smaller fires. The most recent was the 2025 1-4 Fire, which burned 4,322 acres here. In all, 494,171 acres of Mariposa County have burned. Acres are the land each fire burned here, and fires that crossed less than an acre are not counted. Some older or smaller fires may be missing, and a fire perimeter can include unburned patches. How to read fire history