[Isowen]

I think ents are usually destroyed by the peoples of middle-earth. As in The return of the king, Saroman sends orcs to cut down some of the wood from fangorn (did he know they were ents?) They were cut down and when Treebeard takes Merry and Pippin south towards Isengard, they discover the stumps of the ents which were cut down and they mourned them I suppose, in a way. He says something like "These ents were my friends" and "a wizard should know better" So this all leads up to the destruction of Isengard and the imprisonment of Saroman, so I'd say they are more angry than mournful when ents die. Sorry Morsul in the dark, as this post doesn't answer all your questions but maybe some other downer can answer it.