Scientists and land stewards in Sierra Nevada are alarmed about the frequency and ferocity of mountain wildfires in recent years. Drought, insects, forest mismanagement and climate change have combined so far to kill 66 million trees, mostly in the southern part of the range. Tree mortality is expected to reach 100 million by the end of 2016. A scientist says the forest is parched. A tree expert warns of the impending devastation. And a forester has a plan for saving that landscape, one piece at a time. Vic Bedoian reports from Fresno, California.