The incident happened around 9 a.m. near Battlefield and Copp roads in Strasburg, according to the sheriff's office.
Brandon Fingerman captured the flames as he drove through the area.
The highway was temporarily closed at mile marker 295.
As of 2 p.m. the fire had been contained.
Want breaking news in the DMV as it happens, or want to contribute? Join the DMV All Incidents Facebook group.
Click here to follow Daily Voice Fairfax and receive free news updates.