Tobacco

A shrub of which at least one variety was originally introduced into Middle-earth by the Númenóreans, hence its common name of 'westmansweed'. It grew wild in Gondor, where the people enjoyed it for its scent. Eventually it found its way into the more northerly parts of Middle-earth, and the Breelanders discovered that its dried leaves could be smoked in a pipe. This 'art' reached its height among the Hobbits of the Shire, and thus tobacco became commonly referred to as Halfings' Leaf (or simply 'Leaf').

Though tobacco of some form seems to have been relatively plentiful at the end of the Third Age, in later times it must have become extinct in the northwestern regions of Middle-earth, and pipe-smoking was forgotten until it was reinvented much later in history.