Edited sentence: And while they do not die of old age, older ents often become 'treeish', settling down in one place and growing roots and leaves.Eventually, they cease to be conscious and become trees permanently.It is implied that this was the eventual fate of Ents in Middle-earth.While Ents are extremely long-lived, they are not immortal in the same sense as the Elves: they age with the passage of time, albeit very slowly(When invited to sit down, Treebeard tells Merry and Pippin that he is not very 'bendable', while a much younger Ent, Quickbeam, could 'bend and sway like a slender tree in the wind'