LYCOS RETRIEVER 
Saruman: Ent Treebeard
built 276 days ago
Saruman clearly had the ability to understand the minds of the Ents when he found it useful. He managed to talk Treebeard into setting him free from Orthanc by pushing just the right buttons — Ents dislike the concept of caging up any creature.
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Saruman locked himself in the tower, which the Ents were unable to break. He attacked the Ents with liquid fire and fumes from vents and shafts in the grounds of Isengard. The Ents were enraged and they hurled themselves at Orthanc and Saruman responded with an eerie laugh. This caused the Ents to become quiet and determined. They diverted the waters of the River Isen into Isengard and Saruman's fires were quenched and his filth was washed away.
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This all came together after Sauron's fall, when Saruman escaped from the Ents and retired to The Shire and his thug regime in place there. It appears he immediately switched the focus of this operation to wanton destruction: pollution, murder, fire, chopping down trees for no reason. He may have felt this would ... allow him to deal a last blow to Gandalf.
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Saruman ... became acquainted with Treebeard, the eldest of the Ents in nearby Fangorn Forest. He walked in the woods and spoke with Treebeard and learned many things from him, though he did not share information in kind.
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Ent Treebeard