J.R.R. Tolkien called the shepherds of the trees in Middle-earth Ents.
The Ents appear most prominently in The Lord of the Rings, especially in the story of Fangorn Forest. They are ancient, tree-like beings whose name comes from an Old English word meaning “giant.” Their leader, Treebeard, is one of the oldest and most memorable characters in the novel.
The Ents originally lived in Middle-earth alongside the Entwives, who preferred cultivated gardens and settled lands. The Entwives disappeared, and their fate is left unresolved. During the War of the Ring, Treebeard and the Ents decide to attack Isengard after learning how Saruman’s servants have destroyed trees for industry and war.
Ents are sometimes confused with Huorns. Huorns are related tree-beings or animated trees associated with Fangorn, but Tolkien distinguishes them from the speaking Ents. The Eagles are also powerful allies in the story, but they are giant birds rather than tree shepherds.