I'm trying to compile a list of Native British Trees. I have obtained the following list from one site, but it says that some of them are naturalised, rather than native. Can anyone tell me which ones are naturalised from the following please?
Alder (Alnus glutinosa)
Ash (Fraxinus excelsior)
Aspen (Populus tremula)
Bay Willow (Salix pentandra)
Beech (Fagus sylvatica)
Bird Cherry (Prunus padus)
Black Poplar (Populus nigra)
Box (Buxus sempervirens)
Crab Apple (Malus sylvestris)
Crack Willow (Salix fragilis)
Downy Birch (Betula pubescens)
English Elm (Ulmus procera)
Field Maple (Acer campestre)
Goat Willow (Salix caprea)
Hawthorn (Crataegus monogyna)
Hornbeam (Carpinus betula)
Large-leaved Lime (Tilia platyphyllos)
Osier (Salix viminalis)
Pedunculate Oak (Quercus robur)
Purple Willow (Salix purpurea)
Rowan (Sorbus aucuparia)
Scots Pine (Pinus sylvestris)
Sessile Oak (Quercus petraea)
Silver Birch (Betual pendula)
Small-leaved Lime (Tilia cordata)
Smooth-leaved Elm (Ulmus carpinifolia)
Whitebeam - common (Sorbus aria)
White Willow (Salix alba)
Wild Cherry (Prunus avium)
Wild Pear (Pyrus pyraster)
Wild Service Tree (Sorbus torminalias)
Wych Elm (Ulmus glabra)
Yew (Taxus baccata)
Also, if I have missed any Native British Trees (i.e, not shrubs or other naturalised trees), I'd be most greatful in learning what they are.
Many thanks.