Maybe they were jerkin’ you around, maybe they didn’t know themselves.
Suffice to say that I’ve killed many a tree, undesirable species that were growing in commercial forests.
I’ve seen trucks loaded with five-gallon buckets of Velpar, Tordon and other herbicides, but I’ve never seen a truck of salt headed for the woods.
That’s not to say that enough salt, applied in repeated applications, won’t kill a tree. It simply a hard, impractical way to do it when we have miracles of modern chemistry available to do the job easily, quickly, and with deadly efficiency.