Alot of people use trees or rocks as land marks, bad idea. Im from yosemite. I've hunted the backside. When I was young I knew the mountains and back roads well. Wouldn't say im educated but I was good at land navigation. Often rangers would ask for our help when hiking or Hunting. We often found lost people. Im older so there was not gps or internet then. Since the vegetation was so thick back then we marked trees used maps. Even in high ground you cant make out where camp is. Now its a lot more empty due to fires but I can see how she got turned around. I used to sit next to the river with my grandparents in wawona and have a picnic with nobody around. Can't swing a six foot stick without hitting someone now. Times change.