Notes From Nature Talk
searching Las Encinas, I found an expedition account: http://images.peabody.yale.edu/lepsoc/jls/1950s/1959/1959-13(4)229-Patterson.pdf
#no-info only a det. tag
Sonora Pass is a county line, so we don't know if this is in Tuolumne or Mono County.
I think this is Santiago Canyon near Modjeska in Orange County California, but that's a lot of interpretation on my part.