Maybe they are the trees in the Old Forest like Old Man Willow. Except it's called Old MAN Willow and not Old WOMAN Willow, so that doesn't seem right. They are probably too big to have gone across the sea, so they are most likely still in Middle Earth. The Old Forest would be a plausible guess.
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They were not treeish in the beginning. Yavanna (I think) created them to protect the trees of Arda from Dwarves and Orcs. They just over time came to look like the trees they protected. I don't think that they could get so treeish as to not even be Ents anymore.
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I think that the Entwives sailing away in boats would have been noteworthy to some and would not have been an unknown think to the Ents, so we need another theory!
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Mabby in Mirkwood staying with the elves that is not to far away from fangorn forest. Or maby they are in Forlindon (North Lindon) past the Grey Havens right behind the Blue Mountains. There is a forest there right up agenst the edge of the mountain.
Cool. Okay, so on the Ent essay we got of Tolkien Wiki, it says that Sam said that his friend saw a giant treelike figure in the forest near the shire. Maybe that was an Entwife?
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It didn't actually clearly state that the Entwives were female. It is just assumed because it is entWIVES. Also, it would not make sense for them to seed like normal trees, for they do not have much in common with trees other then appearance. Yavanna, a Valar, created the Ents to protect the trees of Middle Earth from Dwarves and Orcs. Over time they began to look like the trees they kept watch over. They are not actually trees in any way. Sir Cody, if you thought that there was no specific genders of Ents because you thought that they were like real trees, you are mistaken. Ents are NOT trees.
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They were gurds for the forest not animals listen to what Illuvatar just said. They took on the aspect of trees over the years they guarded them and when they drank the water there they grew very very tall!
They were animals not plants you are wrong Olorin. They are animals. Men are animals, Elves are animals, Dwarves are animals. And so are the ents. So Sir Cody, you were correct.
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I guess the word animal does technical mean that. And they are all animals. But I do not like to think of Elves and men and what not as animals. I am sure you do not either Eru. So don't be so technical. No body likes a smart alek.