Grass-legume mixtures are always desirable because of their complementary functions in providing nutritive, succulent, palatable forage for the grazing animals. In addition, they are capable of creating much greater quantities of digestable dry matter and protein throughout the growing season than either component. Legumes usually maintain their quality better than grasses even at maturity, and being rich in protein, enhance the forage value, and also add substantially the much needed nitrogen to the soil. The mixtures also improves the physical conditions of the soil, check soil erosion, resist the encroachment of weeds and withstand the vagaries of weather better than pure stands. They also help to check the spread of certain diseases and insect pests. Some of the important grass-legume mixtures are given below :

According to the land-utilization statistics, the area under permanent pastures and grasslands is 13 million hectares. In addition, there are another 15 million hectares classified as cultivable wasteland, and still another 7-8 million hectares under the saline and alkaline soils. This large area, comprising areas effected by soil acidity, salinity and alkalinity, droughts, floods and ravines, can be utilized for the growing of various fodder species.

The grasslands of our country are essentially the monsoon grasslands and the grasses in them show their best biological potential for a period of about four months, after which owing to moisture stress and the advent of winter, the grasses enter dormancy till the next monsoon.

The grasslands normally considered to be the cheapest source of animal feed are in a degraded and denuded state because of overgrazing and faulty management over the ages. Thus the amelioration of the natural grasslands and pastures deserve special and careful attention and priority in our drive for increasing forage production. The Grassland Survey carried out by the Indian Council of Agricultural Research has led to the recognition of four distinct grass covers in the plains and the lower hills and one at high altitudes. Information, in brief, on these grasslands and their important forage species is given below :

Four main grass covers have been recognized in the tropical and subtropical parts of the country. Details of the climate, area, rainfall, elevation, soil type, the present level of production and production potential of the four covers are given in Table 6.

Dichanthium-Cenchrus-Lasiurus cover is distributed in northern Gujarat, Rajasthan, excluding, the Aravalli ranges, western Uttar Pradesh, Delhi, Haryana, Punjab and part of Jammu. The chief forage species are Dichanthium annulatum, Cenchrus ciliaris, C. setigerus, Lasiurus sindicus and Sporobolus marginatus.

Sehima-Dichanthium is the largest grassland cover and is distributed in the Central Plateau, Chhota Nagpur, the Aravalli ranges, Andhra Pradesh, Gujarat, Kerala, Madhya Pradesh, Maharashtra, Orissa, Tamil Nadu, south-west Bengal, southern Bihar, the eastern hilly portion of Uttar Pradesh and Rajasthan. The dominant forage species are Sehima nevosum, Dichanthium annulatum, Iseilema laxum, Ischaemum indicum, Themeda triandra, Chrysopogon fulvus and Heteropogon contortus.

The third, Phragmites-Saccharum-Imperata cover mainly consists of tall coarse species exclusively utilized for thatching huts and in rope-making. It is found in the humid and per-humid regions of the Gangetic Plains and in the Brahmaputra Valley. The chief species are Phragmites karka, Saccharum spontaneum, Erianthus munja, Imperata cylindrica.

The fourth cover, Themeda-Arundinella is distributed in Manipur, Assam, West Bengal, Uttar Pradesh, Punjab, Himachal Pradesh, Jammu and Kashmir up to an altitude of 2,100 metres. Important economic grass species of this cover are Themeda anathera, Arundinella nepalensis, Chrysopogon fulvus, Heteropogon contortus, etc.