The ascribed time period downplayed the South's race consciousness and overplayed it's class consciousness. The extreme attitudes towards an individual in her situation could happen in real life but would they in this cultural context.
Also, the screen write may have stretched realistic fiction that someone illiterate and from what it appeared, to be in later adolescents, taught to read by her boyfriend,, in a year or so have a publishing agency accept her swamp ecology book.
With this said, I liked the overall making.