It's the head and face that especially baffle my mind, and the total package always seems to meld into something like the Wizard of Oz example that was given earlier.
Someone asked about the Entwives earlier, and that was something that I wondered about as well. There seemed to be some emphasis on the Entwives in this chapter, to the point that in the back of your mind, from that part onward, you wondered if Tolkien would produce them somewhere in the story. Otherwise why bring them up in that way?
If he did bring them up later, I missed it totally. But I did wonder about the Old Forest (bordering the Shire), where there were animated trees (one that almost devoured one of the Hobbits). Tom Bombadil's region. There wasn't (to my memory) any reference that would make one think that those "animated" trees in the Old Forest were Entwives, but it did cross my mind that this was the only other place where we ran into trees (or tree-like creatures) that were animated.
I don't have trouble imagining the head and face, it's easy enough to see a face in a gnarled old oak or poplar, what with all those knots and lumps and things that they get.
I think maybe the entwives are definitely MIA.