The ecoregion extends from Bhutan to Nepal, traversing the Siwalik Hills, the southernmost Himalayan range. The southwest monsoon brings rainfall up to 2,000 mm per year, being wetter in the east. These broadleaf forests, lying between 500 and 1,000 m along the Himalayan foothills, range from mixed deciduous forests to subtropical wet hill forests. The forests are tall and trees can reach 30 to even 50 m in height. The dominant trees include Sal, or Shorea robusta, and species of Terminalia, Bauhinia, Schima, and Castanopsis, which are typical of Asian subtropical and tropical forests. Climbers and epiphytes are common in the denser forests.