arrive. Presently large tracts of the mountains are covered with a mixed vegetation resulting from the capacity of the efficient shifting agricultural system being exceeded. As a result, large areas end up becoming dominated by Imperata cylindrica grass, which is used throughout Thailand as roofing material. Cattle can graze on the grass to an extent, as agricultural science research in the 1970s showed. The longer term environmental care of the region is associated with forestry and in the lower reaches, perennial fruit like peaches and other trees. Some projects for the restoration of forest cover have been undertaken in ecologically degraded areas. See also Doi Inthanon, the highest mountain in Thailand Doi Nang Non, a karstic formation in Chiang Rai province Golden Triangle (Southeast Asia) Deforestation in Thailand Highland People Discovery Museum in Chiang Mai Western Forest Complex Southeast Asian Massif Zomia (geography) References External links Opium, Power, People: Anthropological Understandings of an Opium Interdiction Project in Thailand Dubious Development Concepts in the Thai Highlands: The Chao Khao in Transition Cultural Landscape of the northern Region of Thailand (ภาคเหนือ) Golden Triangle and beyond Speciation and Radiation in a River Premier orders urgent action to tackle haze in North Mountain ranges of Thailand Regions of Thailand Natural regions of Asia Highlands