Native woodland
After the end of the last ice-age, trees spread over the land and a natural, native woodland came to cover most of the island. This native woodland has now practically disappeared, chopped down for fuel and for land clearance in preparation for agriculture. Clearance of the woods began a long time ago with the arrival of the Neolithic people in Ireland some 5900 years ago, followed by successive migrations of later peoples with increasingly sophisticated technologies, so that effectively Ireland had lost all its natural woodland, save for a few small remnants, by 1700.
The main component tree species of the native Irish woodland were
| Elm | Ulmus glabra |
| Oak | Quercus petraea and Q. robur |
| Hazel | Corylus avellana |
| Birch | Betula pubescens and B. pendula |
| Rowan | Sorbus aucuparia |
| Scots Pine | Pinus sylvestris |
| Ash | Fraxinus excelsior |
| Yew | Taxus baccata |
| Alder | Alnus glutinosa |
| Holly | Ilex aquifolium |
A few small remnants of native woodland survive in Northern Ireland, usually conserved as nature reserves. Good examples are at Rostrevor, Co Down; Breen, Co Antrim; Boorin Wood, Co Tyrone.