The grass fire threatened one house but was contained, charring about 12 acres and damaging the power poles and a railroad crossing sign. Power was shut off around the burning area for a short period time due to the damage on power line poles.
Four engines from the Tracy Fire Department and one Cal Fire engine brought the fire under control in about 15 minutes as they hit smoldering hot spots for about an hour or so.
Lammers Road was shut down for a time near the fire scene as crews doused the fire along the road and burning poles.



So have matches.
I think maybe someone threw out a cigarette out a window of a car. Or they were doing yard work at the one home, maybe as simple as a spark??
Thanks TFD!