Publication Date June 19, 2016 | NBC Bay Area

Calif. Drought Continues to Raise Fears

United States
A sign from wetter times warns people not to dive from a bridge over the Kern River, which has been dried up by water diversion projects and little rain, on February 4, 2014 in Bakersfield, California. Photo: Associated Press
A sign from wetter times warns people not to dive from a bridge over the Kern River, which has been dried up by water diversion projects and little rain, on February 4, 2014 in Bakersfield, California. Photo: Associated Press

California's drought and a bark beetle epidemic have caused the largest die-off of Sierra Nevada forests in modern history, raising fears that trees could come crashing down on people or fuel deadly wildfires that could wipe out mountain communities.

Aerial images show vast forests that have turned a rust-color. The epidemic has killed an estimated 40 million trees since 2010 in the central and southern Sierra, and it's spreading north...

Last year alone 29 million trees died at the height of California's drought now in its fifth year, the U.S. Forest Service reports. Officials say they'll soon release an updated count.

Drought makes trees vulnerable to the insects' attack, officials say.

A beetle epidemic in forests of the Rocky Mountain states was blamed in 2013 for contributing to Colorado's second largest wildfire, forcing entire communities to be evacuated, said Jeff Mai, aerial survey manager for the U.S. Forest Service based in Colorado