J.R.R. Tolkien called the tree-like race in The Lord of the Rings the Ents.
Ents are ancient, sentient beings who resemble trees and guard the forests of Middle-earth. Their most prominent leader is Treebeard, known in Sindarin as Fangorn. The Ents appear most memorably in The Two Towers, where they respond to the destruction caused by Saruman’s industrial expansion.
Their march on Isengard is one of the trilogy’s major turning points. The Ents destroy Saruman’s stronghold and help end his military threat, although Treebeard explains that Ents are slow to make decisions because they are “not hasty” people.
The word “ent” comes from an Old English term meaning giant or monstrous being. Tolkien adapted the word for his tree shepherds, while also drawing on older traditions of talking trees and forests. Ents are not the same as the giant Huorns, although Tolkien’s texts leave their precise relationship partly mysterious.