Hark, hark, the dogwood does "bark".
The Barking Dogwood is an animated form of dogwood tree residing on the Isle of Wonder.
Background[]
The tree is near the swampland, and part of its trunk is shaped like a dog's head. The head actually barks, and doesn't seem to like anyone getting too close. Alexander wondered if its "bark" was worse than its bite.
Behind the scenes[]
The dogwood tree is given the name 'Barking Dogwood' in the King's Questions.
Not quite an ent, but certaintly similar animated tree.