A 72-year-old woman from Forest Knolls died in a car accident last Monday when her car veered off the road and struck a tree in Samuel P. Taylor State Park. Nancy Jacobsen, a valley resident of nearly 50 years, had recently retired from a career as a computer consultant. Her dog survived the crash and helped lead to the discovery of her body. “For reasons unknown, she left the roadway,” said Roger Fielding, the chief deputy coroner for Marin. “We’re trying to determine if she suffered a medical collapse or if her death was related to the traffic collision.” The crash was discovered by a passing driver, who stopped to help Ms. Jacobsen’s labradoodle, which was running around on Sir Francis Drake Boulevard. The dog led the passerby down to the vehicle, which had landed about 30 feet off the road. When first responders arrived, Ms. Jacobsen was pronounced dead at the scene. Because her Subaru Forester was not visible from the road, investigators don’t know exactly when the collision occurred, said California Highway Patrol spokesman Andrew Barclay. “We do believe it was within the prior 24 hours from when we responded,” he said. Jim Jacobsen, Ms. Jacobsen’s husband of 51 years, said his wife was returning that afternoon from a visit to Jenner. He added that she had been enjoying retirement with some of her favorite activities: sewing, baking and reading.