Alien tree species along the coast of Helgeland, N Norway - a heritage of the landlord Isach Coldevin.
Europe's ancient forests have been extensively logged over a long period of time, and gradually new forests have been planted. In Norway the forests after World War II were largely replaced by the alien species Sitka spruce Picea sicthensis. In Helgeland, Nordland county, Isach Coldevin's idealism lead to a massive afforestation during the first part of the 20th century, and during the second half of the century particularly Sitka spruce was planted. Biodiversity was not recorded before planting, but the ecological changes in the areas planted indicate great loss of biodiversity, particularly in what had been rich pastures and coastal heathlands. Possible dissemination and threat to other species were not taken seriously until a bit into this century. The first "Black List" was published in 2006, and in the latest edition a number of foreign trees got evaluations in the highest threat category. More than a century of experience with introduced species in Helgeland shows clearly how devastating these plantings have been. Anyone who wants to plant Sitka spruce today, or other introduced species, has to apply to the County governor according to a new regulation of 2012.