Green Thumb is a young-adult novel by Rob Thomas, creator of the television series Veronica Mars. It was published in 1999
Pudgy misanthropic boy genius Grady Jacobs wins a scholarship to participate in rainforest research and conservation. Upon discovering that our Grady is only thirteen, Dr. Carter, the scientist in charge, relegates him to the position of camp drudge. A healthier diet and much menial labor transforms Grady both physically and emotionally, making him a better and more complete boy by the end of the book.
To add interest, during the course of his duties, Grady discovers a way to communicate with trees. This fantastic, pseudo-scientific power eventually comes in useful when it is discovered that Dr. Carter's project would in fact lead to the destruction of the rainforest. Grady escapes in the company of Amazonian natives and hatches a daring plan to thwart the evil scientist.
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