Complex sentence: Small populations are also found further south, as a botanical vestige of the Ice Ages; they are found in Germany's Weser and Elbe valleys, under legal protection, and at isolated sites in the English Pennines and the Scottish highlands.
Split into simpler sentences: Small populations are also found further south as a botanical vestige of the Ice Ages. They are under legal protection in Germany's Weser and Elbe valleys, and at isolated sites in the English Pennines and Scottish Highlands.