What kind of beetle is this?
The insect is a bit crunched to be certain. But I suspect it is the California root borer, Prionus californica. The larvae (young) are root borers of deciduous trees. See https://wiki.bugwood.org/HPIPM:Prionus_Longhorn_Beetles.
If not a Prionus, the other choice is the Ponderous borer, Ergates spiculatus. Its hosts are fallen trees of Ponderosa pine and Douglas-fir. See https://wiki.bugwood.org/HPIPM:Ponderous_Borer