U.S. Forest Service investigators have determined the cause of the Ferguson Fire to be vehicle-related. Specifically, investigators believe superheated pieces of a catalytic converter came into contact with dry, roadside vegetation, igniting the fire.

The Ferguson Fire started on the evening of Friday, July 13, along Highway 140 (South Fork of the Merced River) in the Sierra National Forest in Mariposa County. The fire burned 96,901 acres of the Sierra National Forest, Stanislaus National Forest, Yosemite National Park, and state lands. It was declared fully contained on Aug. 22, 2018.

A vehicle associated with the cause has not been located. However, officials are asking anyone with information to contact the Sierra National Forest at (559) 297-0706. The fire began along eastbound Highway 140 near Savage’s Trading Post at approximately 8:00-8:25pm on Friday, July 13.

U.S. Forest Service fire investigators were assisted in the investigation by the National Park Service and CAL FIRE.
Motorists are responsible for many of the wildfires sparked along our roadways. Nearly all these fires could be prevented with proper vehicle maintenance and safety measures:

• Practice safe towing – Secure Chains
• Maintain your Vehicle – Be sure there are no Dragging Parts
• Maintain Tires – Check Tire Pressure and Tread
• Carry a fire extinguisher
• Do not drive or park on dry grass or brush

Help prevent wildfires by following the simple steps above, and outlined in our “One Less Spark = One Less Wildfire,” campaign.