The habitats where true iceland lichen~(Cetraria islandica) grows:

Alpine and subalpine calcareous grassland
Blanket bog
Brownfield
High montane heath and snow bed
Limestone pavement
Lowland calcareous grassland
Lowland dry acid grassland
Montane dwarf shrub heath
Mountain ledge
Raised bog
Upland acid grassland
Upland acid rush pasture
Upland calcareous grassland
Upland dry heath
Valley mire