''Let your fiction grow out of the land beneath your feet.'' Willa Cather''s remark describes her own reasons for re-creating in her works the Nebraska frontier of her youth. Set on the vast northern Great Plains, where the earth has only recently come beneath the plow, the stories and novels in this Library of America volume partake of an impressive physical space and a uniquely American ethnic. Panoramas of lonely prairie and open sky reflect the heroic aspirations and stoicism of her characters and the rebelliousness of their spirit. The Troll Garden (1905) was Cather''s first book of fiction. It contains seven stories, including the justly famous ''Paul''s Case,'' a study of a young man who escapes the world of the ordinary and briefly tastes the life of romance. Also included is ''The Sculptor''s Funeral,'' about a world-famous young artist who remains without honor in his native town. O Pioneers! (1913) is the story of a young Swedish-American girl, Alexandra Bergson, who is left
