I am trying to find a short story I read years ago in an edition of the mammoth book of new sci fi. In the story a sister is visiting her brother, this brother has become physically modified in order to live symbiotically with trees. The modifications mean that her brother has become dependent on a particular tree, which he lives with in a symbiotic relationship. The modifications made to the brother's body mean that he can no longer eat and he is dependent on being kept alive by the tree. The brother is one of a number of people who have chosen to take this step in the idealist belief that life with the trees will prove fulfilling and instructive. The sister visits her brother for the first time only to find that he is ill-treated by the tree, the tree whips him and basically uses him like a slave. The brother cannot escape his fate of now being trapped in this horrible life. Any help gratefully received, I've been thinking of this story for years and years and would love to read it again.
Into Greenwood by Jim Grimsley?
But the best story in the collection, in my opinion, is Jim Grimsley's haunting "Into Greenwood." This tale takes place on a planet where neutered, genetically altered humans serve as symbionts for a race of intelligent trees. "Into Greenwood" is a superb blend of a compelling sci-fi concept, great character development, and wonderful descriptive writing. I recommend "Science Fiction: The Best of 2001" both for pleasure reading and as a classroom literature text.