Others
Orcs and Trolls fled to the far east, and never really recovered. Either during Eldarion's rule or near the end of Aragorn's, there was some talk of "Orc-cults" although these seem to have been founded and run by humans.
The future of the Ents and Huorns is unclear. Aragorn granted them Fangorn Forest as an enclave and gave them permission to expand the forest again west into the vast wastes of Eriador where once a vast primeval forest had spread, but Treebeard lamented that while the forests may spread again the Ents would not, as the entwives had not been found up to date. Over time they dwindled off and more of them became increasingly "tree-ish" and it does not appear that they ever enter into the affairs of other races again (it is unclear if a non-communicative tree-ish Ent can be considered "dead" or if in a sense they persist to the present day).
Dragons will be still present but they will not interfere until later ages according to letter 144 of Tolkien. Some stray answers. Dragons. They had not stopped; since they were active in far later times, close to our own. Have I said anything to suggest the final ending of dragons? If so it should be altered. The only passage I can think of is Vol.I p. 70: ‘there is not now any dragon left on earth in which the old fire is hot enough’. But that implies, I think, that there are still dragons, if not of full primeval stature….-
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