The Northwestern thorn scrub forests are a xeric shrubland ecoregion of Pakistan and northwestern India, stretching along the border lowlands and hills between the two countries. Once covered in deciduous forest, this ecoregion has been degraded through agriculture and the extraction of timber so that it currently has a scanty covering of thorny scrub dominated by such trees as Acacia senegal, Acacia leucophloea and Prosopis cineraria. Where the soils are particularly saline, there are patches of semi-desert. A number of mammals are found in this habitat and about four hundred species of bird. Some small areas are protected but the collection of firewood and the conversion of the land to subsistence farming continues.