The Elfstones of Shannara (1982)

Ancient, ultimate evil threaterned the Elves and the Races of Man. For the Ellcrys, the tree created by long-lost elven magic, was dying, losing the spell of Forbidding that locked the hordes of ravening Demons away from Earth. Already the Reaper, most fearsome of demons, was free. Only one source of protection was powerful enough to stop it: The Elfstones of Shannara. The stones and the right to use them belonged to Wil Olmsford, given him by his grandfather Shea. Allanon, legendary Druid guardian, summoned him from his studies in Storlock to protect Amberle, the elven girl who must carry a sees of the tree to the mysterious Bloodfire, life-source of earth, there to be quickened and to creat a new Ellcrys. While Allanon and the Elves fight a hopeless war against the emerging demons, Wil and Amberle plunge forward in a seemingly impossible quest to find the Bloodfire.