Quickbeam

Tolkien consistently implies that Quickbeam is one of the younger Ents, but where Ents are concerned, 'young' is a very relative term. Quickbeam says of himself that he was an Enting 'many many years ago in the quiet of the world'. This is rather cryptic, but it can be taken to suggest that he was alive during the First Age. (Quickbeam's quote comes from The Two Towers IV 3 Treebeard).

'Quickbeam' is also a traditional name for the tree known as the rowan or mountain ash, and given that this Ent had a particular fondness for rowan-trees, the choice of this name was doubtless intended to emphasise the connection. In modern English, a 'beam' is a broad branch of a tree, but in Old English béam could also refer to the tree itself. So 'Quickbeam' is more literally 'quick tree', which is also the meaning of this Ent's Elvish name of Bregalad.