Complex sentence: Considered to be an indicator of agriculture in pollen diagrams, "P. lanceolata" has been found in western Norway from the Early Neolithic onwards, something considered an indicator of grazing in that area.
Split into simpler sentences: Considered to be an indicator of agriculture in pollen diagrams, "P. lanceolata" has been found in western Norway from the Early Neolithic onwards. Something that is considered to be an indicator of grazing in that area.