Four acres of vegetation burned and a man suffered minor injuries when the tractor he was driving caught fire east of Modesto on Thursday.
The man was riding the tractor at the old landfill on Geer Road near the Tuolumne River.
Stanislaus Consolidated Fire Protection District Battalion Chief Kevin Wise said the fire ignited when the tractor hit a rock at 1:30 p.m.
It burned the driver's face, but he refused medical treatment at the scene.
The Oakdale Fire Department and Hughson and Keyes fire protection districts joined Stanislaus Consolidated in battling the blaze, which took about 45 minutes to contain.