Below the Root
1975 Atheneum

First book of the Green Sky Trilogy

Born in a future world, on a planet covered by enormous trees, Raamo begins to learn the hidden truths that underlie his beautiful but secretive civilization.

Tor edition 1985
Computer game "Below the Root"--Spinnaker Software's Windham Classics 1985 for for Apple, IBM and Commodore
Junior Literary Guild Selection
Dell Laurel Leaf Edition 1992

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Zilpha adapted the Green Sky trilogy to form the basis of a computer game, "Below the Root". It was released by Spinnaker Software in 1984 and is now considered a classic. The game is still playable by means of emulator software, which can be downloaded online.