It was the largest recorded wildfire in California history and a just-released investigation reveals it was accidentally started by a rancher trying to kill some wasps.
Investigators say the Ranch Fire started when the man, based three hours north of San Francisco, came upon a nest of wasps buried underground last July.
The rancher, Glenn Kile, is allergic to wasp stings, so he took a metal stake and pounded it into the ground to try to seal the nest off, according to The New York Times. Unfortunately, a single spark flew up and ignited dry grass on his property.
"I smelled smoke, I turned around, and there it was. There was nothing I could do,” he told The New York Times. “Mother Nature, you have no control."
The fire then destroyed 150 homes with 410,203 acres going up in smoke, half the size of Rhode Island. A firefighter was killed when a tree fell on him.
In the report released this week by Cal Fire, Kile was said to be found responsible for the fire but not negligent. He made an innocent mistake.