LPM 121: Fodder Production and Grassland Management (1+1)

GRAZING MANAGEMENT

• Since a smaller number of well fed animals is always better than a large number of half starved ones, a strict control of the number of animals let in for grazing is the first principle of all grazing systems.
• In fixing the number of animals, the carrying capacity of the grassland should be taken into consideration. This is defined as the number of animals that can graze in a unit area without over grazing or undergrazing in an average season.
• The greatest single factor which causes determination of grasslands is over-grazing on account of selective grazing habit of animals, desirable species tend to get depleted much faster than the less palatable species.
• To avoid this risk, grazing must be stopped at some stage or other i.e., in grassland terminology the grazing has to be deferred since it will seldom possible to stop grazing over entire area, when no other alternative areas are available.
• The practical method is to defer grazing in a part of the grassland and to allow grazing in the other part in a 'rotational' system.
• Over grazing deteriorates the grasslands. Just like human beings, grazing animals, too, have their likes and dislikes and certain grasses are preferred while certain others are avoided.
• On account of the relative grazing habit, desirable species tend to get depleted in grasslands much faster than other species that are not so palatable.
• In most perennial grasses, new shoots are produced by utilizing the reserve food material that is stored in the underground parts. Before the new growths are in a position to build up food reserves by their own photosynthetic activity, there is a stage in the life history of the perennial plant when the food reserves are at their minimum.
• When the plant produces food material in excess of its growth requirements, the surplus is translocated in to storage organs. At the commencement of next growing season this surplus is utilized for the production of new shoots.
• Under grazing conditions these fresh shoots get removed by the grazing animals and the plant never get a chance to build up any reserve food material. There is thus a continuous drain on the food reserves of the plant, so that at the next growing period, the plant has to start with greatly depleted food reserves. If this over grazing continues, the food reserves get exhausted soon and the plant becomes weaker and weaker and ultimately dies.
• Hence in grasslands, it is essential to allow the plants to build up their food reserves before the forage is utilized for grazing purposes.
• In the case of annual plants, which can continue to exist only through seed formation and germination of that seed each year, the correct management of grasslands dominated by animals is to cut it for forage only after the seed formation stage.