I'm not sure about the meaning of the phrase "pluck back" in this passage of Margaret Mead's Sex and Temperament in Three Primitive Societies.
The ghosts themselves are residents of the lands, and a man going upon his own inherited land will announce himself, his name and relationship to them, remarking: "It is I, your grandson, of Kanehoibis. I have come to cut some posts for my house. Do not object to my presence, nor to my timber-cutting. As I return, pluck back the brambles from my path, and bend back the branches so that I walk easily." This he must do even if he goes along on the land that he inherited from his forefathers.
I know the meaning of pluck with regards to plants meaning to pull out/rip.