I never even heard of a "salvage" yard until later in adulthood. We always went to the junkyard or boneyard when I was hot rodding back in the 60's and 70's and even with my father in the 50's. Our first hemi came from a local junkyard for the total sum of $50 which was "junk price."
I really think junk meant salvage back then. Junk wasn't "trash" or "garbage." Garbage went to the "dump," because we didn't know what a landfill was back then either.