Lightning-sparked wildfires killed thousands of giant sequoias this year, adding to a staggering two-year death toll that accounts for up to nearly a fifth of Earth’s largest trees, officials said Friday.

A former college professor was indicted by a federal grand jury Thursday for allegedly starting four wildfires in Northern California earlier this year that threatened to trap firefighters as they battled a massive fire nearby, federal prosecutors said.

A woman accused of starting a California wildfire that destroyed more than 100 homes was deemed incompetent to stand trial after she was evaluated by two court-appointed psychologists. 

Monday marked the third anniversary of the Camp Fire, not just the state's deadliest and costliest wildfire, but a defining moment for the climate change argument, the state's limited resources, and the fate of PG&E.