Grasslands exhibit characteristics between a forest and a desert. Grasslands associated with a forest may show a few large trees. A Horton plane is an example of this. Grasslands can be found in every type of climatic zone. They are of four types
Wet Patanas
Dry Patanas
Damana and Talawa
Villus
Grasslands are important ecosystems as they are the main catchment areas as well as grazing grounds for animals.
Wet Patanas
They are located around 2000m. Above sea level. Rainfall is high and well distributed. Therefore they are moist throughout the year. These are close to the forests hence the dominant species is often is a Montane forest tree type. Some example of wet patanas are Horton planes, Elk planes, Moon planes, Sita eliya, Bogawanthalawa and Bopath thalawa. Apart from grass, there are isolated trees. Dominants are Ratmal Rhodedendron. The main trunks and branches of these trees are covered with the epiphyte Usnea ( Old man’s beard ). In addition Cyperus species and the fern Pteridum are commonly found. Soil is rich in humus.
Dry Patanas
Welimada plateau, Knuckles, Deniyaya and Rakwana are examples of dry patanas. Except for small patches of forests in the valleys, the rest of the area is covered with this type of grasslands. The characteristic grass variety is Mana ( Cymbopogan nardus ). Dry patanas are more extensively spread out than wet patanas. Very often in the dry season the grass catch fire resulting in the soil being exposed and consequently getting eroded.
Damana and Talawa
These grasslands are a consequence of chena cultivation. The grasslands of the low country dry zone are called Damana and those in the low country wet zone are called Talawa. They can be seen in Polonnaruwa, Welikande, Trincomalee and Kalutara districts. The vegetation consists of grasses such sa Mana, Iluk and Bata (Cane) as well as trees such as Diwul, Palu, Myla and Madam. This ecosystem has a diversity of large grazing and browsing animals like the deer, buffalo and is a popular habitat of elephants.
Villus
These are wet grasslands found in the flood plains of the rivers in the dry zone. In areas where flooding occurs, villus are formed in the abandoned ponds, lakes and large water bodies. Villus is highly fertile ecosystems.
It is very high in biodiversity and density, comprising of large animals such as elephants, deer, buffalo, leopards, foxes, otters and birds such as peacocks, jungle fowl, storks, “Seru”, king fisher’s and hawks and a large range of fish, amphibians and reptiles.
After the rainy season, the villus areas get filled with water plants and make a beautiful scene with the encircling forests. They are a fine attraction for tourists. The villus filled with fish is a rich fishery resource for the villagers. The most extensive villus of Sri Lanka is in the Mahaveli flood plains. Villus grasslands are fine grounds for cattle farming. Examples are the cattle farms of Tamankaduwa.
