The maritime pine ("Pinus pinaster") is found at an intermediate altitude and on generally siliceous soil, which in Galicia goes down to sea level and inland alternates with Pyrenean oak. Over limestone, the black pine ("Pinus nigra" subsp "salzmannii") plays an important role in many of the mountain ranges in the centre, east and south of the Peninsula; in limy soil, and at the same altitude, it usually displaces the former. Both are displaced at higher altitudes by the Scots pine.