Are Ents trees

Answer 1

Yes and no. Ents began as trees... The first one existed when some of the first Elves to be in Middle Earth desired to bring life to everything sang some song and brought some trees to life. The Ents never forgot this.

However, they are no longer "trees," per say. They are the shepherds of trees, and in the movie, Treebeard takes offense to being called a tree by Pippin.

Note also that they are less treelike in the books than in the movie. They are described as being "man-like or troll-like" in shape. Parts of their bodies are covered in something like bark, but their arms are smooth.

The Ents did not start out as trees. They were created by the Vala Yavanna with Eru's permission, to be guardians of the trees and flora of Middle-earth. The Elves taught them how to speak.