If an Ent had Sauron's one master ring, the ring to rule them all, then I believe that it would become the most cynical living creatures. I recall Treebeard saying 'I am on no one's side because no one is on my side', therefore, imagine an Ent, feeling betrayed and abandoned, victimised by Saruman's treachery, having in their possession the one ring. Oh it wouldn't just be devastating, it would be terrifying, it would be scary (assuming of course, that the Ent possessing the ring convinced other Ents his purpose.) Also, let's not forget that the ring can make the one wearing it invinsible, so imagine nature's anger and fury personified, and now imagine it invinsible. First it would be Saruman perhaps, but let's not forget that the ring has a will of its own. Maybe afterwards they'd go after the dwarfs, with their axes that Ents hate. Then it could be the race of men, then the elves, then maybe even the remaining istari. There is no saving yourself from the one ring. Be afraid.

Yeah, the Ents as seen through Treebeard and Quickbeam are a lonely, tired, cynical race. They are isolationist but that's only the men locked away in their dying forests. The women probably helped till the fields and looked nothing like giant walking trees.

Not quite...

If the Ents had been given their own rings originally thats what they would do, but if an Ent was given the ONE ring, it would corrupt it.

It probably would, but the Ents are crazy old and slow so whatever the ring did do to it would take even longer to corrupt than it would an Elf. Ents aren't wizards so I don't know how much power the ring would give it.

The elves wouldn't preserve if they had the one ring. The only reason they were able to preserve using the rings they had is because those rings weren't corrupted by Sauron.

Well, they were corrupted by Sauron when he finally built the one ring to rule them all. Hence the Nazgul.

Not quite, the nazgul were men. Men and dwarves had rings that would corrupt. The nine men became nazgul, but the seven given to dwarves had little effect due to the natural sturdiness of your average dwarf. The only ill effect awarded to the dwarves was an increase in greed and gold-lust.

However, I misspoke earlier. The three rings given to the elves were slightly flawed, in that the owner of the One Ring could see into the minds of whomever wore the three. These rings, however, didn't corrupt the elves.

I'm aware the 9 riders were men, that the dwarves all faded away presumably, and that the remaining elf-rings began to fade rather than corrupt anything.

In that case, I'm highly confused by the intent of comment #120

yeah, Peter Jackson has me all confused. The number of times I've seen his trilogy outweighs my reading of the book and it's taking me time to process. The one ring for the elves is temptation one they are not usually interested in but that seems to be their greatest weakness. Legolas falls prey to it when he gets sucked into Fangorn and again when he pines for the grey haven after spending time by the ocean. Galadriel tempts herself to prove she can resist it and Elrond who magically became an elf for Tolkien's sequel seems to not give a **** OR not trust himself like Gandalf. I guess the most appropriate answer to the question of what an Ent would do with the one ring is would he care? Probably not, Ents have enough going on to concern themselves with magic and conquering and whatnot.