The firefighter was in his gear while operating in a mandatory evacuation zone in the Blands Cover area near the North Pass Fire when he was confronted by a man, according to The Willits News.
The firefighter left the area and Mendocino County Sheriff's deputies moved in.
Firefighters in the county reportedly spot marijuana grows occasionally but typically ignore them and go about suppression efforts.
The firefighter kept fighting the flames until he was approached by a man in a vehicle who ordered him to leave before aiming the shotgun at him, officials told the news station.
Deputies searched the evacuation zone and located a man and vehicle at a residence.
The man admitted to confronting the firefighter and told police he was growing marijuana and decided to stay at the residence instead of obeying the evacuation order.
Veda Bennett-Swank was arrested on suspicion of brandishing a firearm in a threatening manner, interfering with a firefighter at a fire and issuing criminal threats.
FIREFIGHTER THREATENED WHILE WORKING NORTH PASS FIRE JH 09/04/12
A FIREFIGHTER WORKING THE NORTH PASS FIRE WAS THREATENED WITH A GUN NEAR A MARIJUANA GARDEN.
THE CAL FIRE FIREFIGHTER WAS ON A VACANT LOT OF LAND IN THE BLANDS COVE AREA, WHICH IS ALSO PART OF THE MANDATORY EVACUATION AREA.