Upland habitats are high elevation areas (above 1,000 feet, or 300 metres), and include moorland, rough grassland, and rocky outcrops, these latter home to the rarest set of plant species, some of which may be also found in rocky places at lower elevations. Uplands are much more common in the northern half of the UK; further south they are largely restricted to Wales and the moors of the far southwest. Much of these regions were originally covered by trees and shrubs, but were many centuries ago cleared for grazing and agriculture.