Afghanistan is sparse but various. Common trees in the mountains are evergreens, oaks, poplars, wild hazelnuts, almonds, and pistachios. The plains of the north are largely dry, treeless steppes, and those of the southwestern corner are nearly uninhabitable deserts. Common plants in the arid regions include camel thorn, locoweed and wormwood, a mixture of sagebrush. The wild animals of Afghanistan include 125 mammal species, some of which are nearing extinction. The most seriously endangered are the goitered gazelle, leopard, snow leopard, and Bactrian deer. Other wild animals of Afghanistan include Marco Polo sheep, urials, ibex, bears, hyenas, jackals, and mongooses.