List of trees of Great Britain and Ireland
Many lists of Trees of Great Britain and Ireland have been written. There are a number of issues surrounding the inclusion of a species in such a list. As can be seen from the outline of debate below, there is no 'correct' list of trees of Britain and Ireland.
Issues of debate
Definition of species
There are a number of different opinions regarding the validity of some species, notably apomictic microspecies and whether some 'species' may actually be hybrids. In particular, the number and definition of species in the genera Sorbus (rowans, whitebeams etc.), Ulmus (elms) and Salix (willows) are open to debate.
Definition of native
Native species are considered to be species which are today present in the region in question, and have been continuously present in that region since a certain period of time. When applied to Britain and Ireland, three possible definitions of this time constraint are:
- a species that colonised these islands during the retreat of ice at the end of the last ice age
- a species that was present in these islands when the English Channel was created and the land bridge between Britain and continental Europe was flooded
- a species that has colonised without human assistance; in some cases this is uncertain.
The only endemic tree species in Britain and Ireland (that is, that are native only to this region) are some apomictic whitebeams.
Species that were native in the region in prehistory before the last ice age, but not subsequently, are generally regarded as extinct and no longer native.
Many additional species have been imported by humans; the total list of all introduced trees numbers several thousand. A far smaller number of these have become widely naturalised, spreading by their own accord without recourse to further human assistance.
Definition of tree
A tree can be defined as a large, perennial, woody plant with secondary branches supported by a primary stem (compare with shrub). There is no set definition regarding minimum size, though most authors cite a tree species as being one which regularly reaches 6 m (20 ft) tall (see also tree).
List of species
- Common Ash (Fraxinus excelsior)
- Cherries and Plums
- Lindens (Limes)
- Rowans and Whitebeams
- Willows (Salix spp.; several species)
Native large shrubs
These larger shrubs occasionally reach tree size:
- Alder Buckthorn (Rhamnus frangula)
- Purging Buckthorn (Rhamnus cathartica)
- Elder (Sambucus nigra)
- Common Dogwood (Cornus sanguinea)
- Rock Whitebeam (Sorbus rupicola)
- (Common) Sea-buckthorn (Hippophae rhamnoides)
- Spindle (Euonymus europaeus)
- Sallow, Goat Willow (Salix caprea)
- Grey Willow (Salix cinerea)
- Purple Willow (Salix purpurea)
- Common Osier (Salix viminalis)
- Eared Willow (Salix aurita)
- Guelder Rose (Viburnum opulus)
- Wayfaring tree (Viburnum lantana)
- Privet (Ligustrum vulgare)
- From Europe
- Maritime Pine (Pinus pinaster; rarely)
- European Black Pine (Pinus nigra; rarely)
- Norway Spruce (Picea abies; rarely)
- European Larch (Larix decidua)
- European Pear (Pyrus communis; sometimes regarded as native)
- Plymouth Pear (Pyrus cordata; sometimes regarded as native)
- Cherry Plum (Prunus cerasifera)
- Sycamore (Acer pseudoplatanus)
- Norway Maple (Acer platanoides)
- Sweet Chestnut (Castanea sativa; a Roman introduction)
- Holm Oak (Quercus ilex)
- Turkey Oak (Quercus cerris)
- Common Horse-chestnut (Aesculus hippocastanum)
- English Elm (Ulmus procera; a Roman introduction)
- From Asia
- Japanese Larch (Larix kaempferi)
- From North America
- Lodgepole Pine (Pinus contorta)
- Sitka Spruce (Picea sitchensis)
- Black Spruce (Picea mariana; rarely)
- Douglas-fir (Pseudotsuga menziesii)
- Grand Fir (Abies grandis)
- Western Hemlock (Tsuga heterophylla)
- Western Redcedar (Thuja plicata)
- Lawson's Cypress (Chamaecyparis lawsoniana)
- Monterey Cypress (Cupressus macrocarpa; rarely)
An endemic species is a plant only native to a certain area. Outside this area, unless spread naturally it is considered non-native, usually as a result of cultivation. Britain and Ireland have few endemic trees, most being micro-species of Whitebeam. But there are some interesting endemic trees nevertheless.
- Apomictic Whitebeams endemic to the British Isles:
- Sorbus arranensis – Isle of Arran only.
- Arran Service Tree – Isle of Arran only.
- Sorbus pseudomeinichii - Isle of Arran only.
- Lancaster Whitebeam - Lancaster only.
- English Whitebeam - Great Britain and Ireland only.
- Bristol Whitebeam - Avon Gorge only.
- Devon Whitebeam – Devon, Somerset, Cornwall and Ireland only.
- Ley’s Whitebeam – Brecon Beacons only.
- Lesser Whitebeam – Brecon Beacons only.
- Sorbus leptophylla – endemic to UK
- Sorbus wilmottiana – endemic to UK
- Bloody Whitebeam – Exmoor only.
- Sorbus subcuneata – coastal North Devon and Western Somerset only.
- Cheddar Whitebeam – Cheddar Gorge only.
- “No Parking” Whitebeam – North Devon only.
- Llangollen Whitebeam – Llangollen only.
- Irish Whitebeam – Ireland only.
- Leigh Woods Whitebeam, Leigh Woods only.
- Trees of the world
- Woodland management
- Forestry in the United Kingdom
- British National Vegetation Classification
- The Woodland Trust (UK conservation charity promoting woodland restoration and expansion.)
- Forestry Commission (UK government department responsible for protection and expansion of Britain's forests and woodlands.)
- Elwes, Henry John, and Henry, Augustine, 1906 The trees of Great Britain & Ireland BHL Monograph.Includes rare introduced trees.Seven volumes and seven volumes of excellent black and white plates.
- Tree Council of Ireland Heritage trees