The native pinewoods which formed this westernmost outpost of the boreal forest of post-glacial Europe are estimated to have covered as a vast wilderness of Scots pine , birch , rowan , aspen , juniper , oak and a few other hardy species .
The native pinewoods which formed this westernmost outpost of the boreal forest of Europe are estimated to have covered 15,000 km2 as a vast wilderness of Scots pine , birch , rowan , aspen , juniper , oak and a few other species .