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Dry zone evergreen forests in Sri Lanka and other types of forests

The northern and eastern portions of the island are considerably drier, lying in the rain shadow of the central highlands. The Sri Lanka dry-zone dry evergreen forests are a tropical dry broadleaf forest ecoregion. Several timber species such as Satin, Ebony grows in the region.

Tropical dry forests cover most of the ecoregion, but within the ecoregion there are a number of distinct habitat types (of sub-regional extent). These include patches of submontane savanna and grassland-known locally as talawa-especially along the eastern and southeastern slopes of the central massif. In the northeast, lowland grasslands, locally known as villus, are associated with the floodplains of the river systems. These grasslands provide critical water and fodder for herbivores during the dry season.

Most of this ecoregion was settled and cultivated until about 500 years ago; therefore, the forest is secondary. However, several patches of old-growth forests remain and are included within protected areas (e.g. Wasgomuwa National Park and parts of Ruhuna National Park).

The evergreen dry forests are dominated by Manilkara hexandra, Chloroxylon sweitenia, Drypetes sepiaria, Feronia limonia, Vitex altissima, Syzygium spp., Drypetes sepiaria, and Chukrasia tabularis, with the scrub and regenerating forests characterized by Bauhinia racemosa, Pterospermum suberifolium, Cassia fistula, and Dichrostachys cineria. Acacia thorn scrub grows in disturbed areas.

The talawa savannas are characterized by Terminalia chebula, T. belerica, Pterocarpus marsupium, Butea monosperma, Careya arborea, Anogeissus latifolia, Phyllanthus embilica, and Zizyphus spp.. The dominant grasses in the villus include Cymbopogon spp., Eragrostis spp., Themeda spp., and Imperata spp..

Ritigala, the isolated hill in central Sri Lanka, is a hotspot of endemic species within this ecoregion with several endemic plants such as Madhuca clavata.

Mangroves

The total area of mangrove forests grow in fringing estuaries and lagoons in Sri Lanka cover about 3400 ha. Since this habitat is subjecting to varying salinity, heavy sediment loads, lack of oxygen the ecosystem shows unique characteristics. The vegetation is dominated by salt tolerant species and towards the shore the tolerance increases. These forests protect the coastline, trap sediments, and serve as breeding grounds for many aquatic faunal species. Also these acted as protectors during the tsunami in 2004 by reducing the force of the wave, by minimizing the damage.