way to a subalpine forests of fir (Abies fargesii, A. chensiensis), Cunninghamia, and birch (Betula spp.), with rhododendron (Rhododendron fastigiatum) abundant in the understory. The region is home to a large number of rare plants, of which around 3,000 have so far been documented. Plant and tree species native to the region include Ginkgo, thought to be one of the oldest species of tree in the world, as well as Huashan or Armand pine (Pinus armandii), Huashan shen (Physochlaina infundibularis), Acer miaotaiense and Chinese fir. Timber harvesting reached a peak in the 18th century in the Qinling Mountains. Home to the Qinling pandas, a sub-species of the giant panda, which are protected in the region with the help of the Changqing and Foping nature reserves, between 250 and 280 giant pandas live in the region, which is estimated to represent around a fifth of the entire wild giant panda population. The mountains are also home to the golden takin, golden pheasant, golden snub-nosed monkey, Temminck's tragopan, crested ibis, golden eagle, blackthroat and clouded leopard. The Chinese giant salamander, at the largest amphibian in the world, is critically endangered as it is collected for food and for use in traditional Chinese medicine. An environmental education programme is being undertaken to encourage sustainable management of wild populations in the Qin Mountains and captive breeding programmes have been set up. Weapons of mass destruction According to the Nuclear Information Project, China "keeps most of its nuclear warheads at a central storage facility in the Qinling mountain range, though some are kept at smaller regional storage facilities." See also Gallery road Huaqing Pool Qinling Orogenic Belt Qinling panda References External links Landforms of Shaanxi Mountain ranges of China Regions of China