what was its use in the book?
In the novel's context, it is a song that Katniss learned from her father, and is used as a battlecry
The Hanging Tree (The Hunger Games song)
In the novel's context, it is a song that Katniss learned from her father, and is used as a battlecry. Katniss's mother prohibited the use of the song in her home after hearing Katniss and her sister Primrose chant the song while making necklaces. 
when does katniss sing the hanging tree in the movie UNANSWERABLE from which movie is this? "The Hunger Games" what is the character's full name? Katniss Everdeen what is her name in real life? Jennifer Lawrence who composed the song? James Newton Howard was this movie based on a book? Yes, it is based on "The Hunger Games" trilogy of novels who wrote the book? Suzanne Collins how was the song received? It received positive reviews from music critics, with several critics complimenting its effectiveness as a murder ballad who were the critics? Jeff Baker,  Gabriella Tully Claymore, Stephanie Merry and many others when was the song released? On  9 December 2014
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The Hanging Tree (The Hunger Games song) [SEP] Composition and use in book
In the film, Lawrence performs the song a cappella. In the novel's context, it is a song that Katniss learned from her father, and is used as a battlecry. Katniss's mother prohibited the use of the song in her home after hearing Katniss and her sister Primrose chant the song while making necklaces. Peeta Mellark, Katniss's love interest, associates "The Hanging Tree" with her father; he heard him sing the song once when he traded goods at his parent's bakery.