In the decades since, the wood-boring beetle has spread east and west across the U.S. and Canada, killing tens of millions of ash trees, causing one of the costliest forest insect invasions to date.

But scientists say there is a simple explanation for why some have been spared that fate. A palm tree burns as winds fuel the Eaton Fire in Altadena, Calif., on Wednesday. (David Swanson/Reuters ...

When people think of wildfires, burning trees are likely the first image that comes to mind. So when a city burns and trees are left standing, it may seem unusual at first glance. Several massive ...