This paper examines the characterisation of three conifers: yw (yew), pinus (pine) and ffynidwydd (‘fir’ in the broadest sense) in Middle Welsh sources, as well as the status of these trees in medieval Wales. Pine was likely extremely rare in Wales during the medieval period, but there is some evidence possibly referring to its presence in medieval texts. Yew was declining but more common, both as a naturally occurring species and as individual trees planted in churchyards and abbeys and beside holy wells. Yew gained a reputation for holiness based on these holy trees, and pine gained a separate reputation for holiness based on its appearance in the legend of the rood. All the conifers also seem to have acquired reputations as disruptive, liminal species and may have been included in texts as a sign to the reader that the ordinary rules of the secondary world had been suspended.