Dave Edwards has hiked in the Santa Monica Mountains for decades, but the view has changed in the past few years.

Hundreds, if not thousands, of trees have died, leaving hillsides with gray and brown patches.

http://www.vcstar.com/news/special/outdoors/oak-trees-in-the-santa-monica-mountains-hit-hard-by-drought-38b7b50b-66c9-36d7-e053-0100007ff56c-388960071.html

1. California oak trees.

http://universityofcalifornia.edu/news/15-national-treasures-and-ucla-scientists-working-save-them

Choked with the detritus of at least 70 million dead trees, vast tracts of the landscape have become a botanical emergency room, parched by drought, invaded by damaging insects and infected with a deadly organism that may have piggybacked its way to the state on rhododendron leaves.

http://www.orovillemr.com/general-news/20160827/sudden-oak-death-wiping-out-millions-of-trees-altering-ecosystem