The ecoregion consists of an area of plateau and low river basin in
Cambodia,
Thailand,
Laos,
Vietnam and
Myanmar and includes: • In Thailand the large
Khorat Plateau, the higher elevation plains of the
Chao Phraya River basin, the foothills of the
Tenasserim Hills and other dry areas of the lower slopes of the
Khun Tan,
Phi Pan Nam and
Phetchabun mountain ranges of the north of the country. • In central and southern Laos the wide valley of the
Mekong river system. • In Cambodia a large area of the dry plains of the northern, eastern, and south-central parts of the country. • In Vietnam the uplands of the upper
Tonlé San and
Srepok Rivers. • Adjacent neighboring parts of eastern Myanmar These are the drier areas of
Indochina with 1,000–1,500 mm rainfall per year and a long dry season when regular fires occur in the undergrowth, some set intentionally to clear the forest or drive out wildlife for hunters. Great swathes of this ecoregion are densely populated and are used for agriculture or urban development, especially in Thailand. ==Flora==