From Tolkien Gateway
"Entmoot" by Darrell Sweet
PurposeDiscussion for Ents
Notable membersTreebeard, Bregalad, Beechbone
LocationDerndingle in Fangorn Forest
Notable forLast March of the Ents
GalleryImages of Entmoots

Entmoot was the name for a meeting of the Ents of Fangorn Forest, said to be a rare occasion in the later days of the Third Age. The Moot was held by tradition at a dell in the Forest known as Derndingle.[1]

War of the Ring

During the War of the Ring, Hobbits Meriadoc Brandybuck and Peregrin Took came to the Fangorn Forest and related to Treebeard of the Wizard Saruman's treachery.

Treebeard then summoned an Entmoot which, due to the slow thinking and speech of the Ents, lasted for days, between 30 February and 2 March T.A. 3019.[2]

The long, deliberate discussion led to the decision that -- facing an inevitable slow extinction -- they would attack Isengard to avenge the damage Saruman's Orcs had done to their tree-herds. This 'Last March of the Ents' was a significant event in the War of the Ring.[1]