Veld Management in the Grass Veld
Grass veld management differs based on the type of grass veld whether sweetveld, souveld or mixedveld
Veld management can generally be defined as the science dealing with the utilisation and conservation of the natural veld to ensure maximum animal production without adversely affecting the plant cover. Thus, veld management must be aimed at providing for the requirements of the vegetation, the livestock and the soil.
It must be remembered that there is a natural balance between the vegetation and environmental conditions, namely: climate, soil, and water relations. Under conditions where the natural balance is not disturbed, not only does a stable plant cover occur but moisture and soil conditions are then also optimal.
Of all the factors that influence the natural balance, vegetation is the only factor over which a certain degree of control can be exercised. Good veld management is thus aimed at stabilising the natural vegetation at such a stage that optimum production will be assured without detrimentally affecting the natural balance.
To achieve this objective the aim should be to induce veld improvement or, where the veld is already at the desirable stage (usually the climax stage) to maintain it in this condition. Sometimes, where the climax stage may not be the most desirable from the aspect of livestock production, it may be necessary to stabilise the vegetation at a lower stage. In most farming areas, however, the principal aim is to improve the veld or prevent further deterioration.
Planning must be regarded as the first step in the application of veld management. Planning of veld management depends on a thorough knowledge of the vegetation, its changeability, plant succession, the carrying capacity and quality of the veld, the reaction of the vegetation to grazing and the growth processes and life cycles of plants. A knowledge of the scientific principles is a further important pre-requisite for the planning of a veld management system.
A variety of veld types occur in a region and therefore various grazing systems are recommended for the different veld types.
All veld management systems are aimed at the maintenance of maximum animal production per hectare. To achieve this objective, it is necessary to manage the plant or animal complex in such a way that a compromise between the requirements of plants and animals is obtained. A knowledge of the stock which are grazing the veld, their requirements and habits, are also necessary if the veld is to be utilised in the best possible manner.
Three facets of the process of production must be differentiated as each can have a limiting effect on the final result.
- The production and maintenance of a maximum yield of digestible feed per hectare must be achieved through the application of suitable resting periods;
- An optimum percentage of the available grazing should be utilised by applying efficient grazing management;
- Effective conversion of the grazed fodder must be obtained by using the most suitable animals.
The production of a maximum yield of useful grazing depends to a marked degree on the pattern of rotational rest that is applied. In many veld types, particularly in the drier areas, the veld produces maximum yields when it is grazed not more than once or twice per annum, which necessitates the provision of fairly long rest periods. To allow for long rest periods while at the same time ensuring economic production from the number of animals which are being kept, it is necessary to graze the veld for short periods. The desirable length and frequency of rest will depend on the veld type and condition of the veld. Generally speaking, the more sour the veld, the shorter the rest and the more trampled the veld, the greater the need for long rest periods for seeding purposes. In the same way, the need for highly intensive grazing will, to a large extent, be determined by differences in the palatability of the edible plants comprising the specific veld types. In other words, where the veld is composed virtually of sweet grasses only, as in areas of the Northern Cape, there is little need for high-intensity grazing, but in mixed veld where species selection is a grave problem, heavy grazing for short periods may lead to more efficient utilisation and thus higher animal production per hectare.
All management systems are based on the principle of rotation of stock amongst several camps, primarily to meet the growth requirements of the veld so that it, in turn, can meet the requirements of the animal as far as possible. The basic differences between all systems lie in the frequency and length of grazing and resting periods which then determine the intensity of grazing (animals per hectare for the grazing period). The more camps available, the longer the rest periods be and the shorter the grazing period the less selective the grazing will be. Although a ‘short grazing period or long rest’ system will be beneficial for most veld types from a veld improvement point of view, the desirable degree of intensification will depend on local conditions and the effect of intensification on the type of animal grazing the veld.
Production per animal is invariably highest under low-intensity grazing. Where selective grazing beyond a certain degree is eliminated by high-intensity grazing, a reduction in production per animal can be expected.
Reclamation of Degraded Veld
In the sour grass veld, the high rainfall enables the degraded veld to quickly regain when the grazing pressure is removed. In cases with severe soil erosion, mechanical barriers may be required to help induce siltation and provide a seedbed for pioneer plants. In these typically high-leached soils, applying fertilizers will help promote the establishment of plants. Replacing unpalatable pioneer species with more palatable species is usually a very slow process. Some of these plants will persist in almost pure stands for more than 20 years. Re-seeding such pioneer stands with seeds from more desirable species such as Themeda triandra has resulted in limited improvement. Resting and spring-burning practices may also favour T. triandra species. In areas with favourable soil conditions, complete replacement of the veld by the establishment of a permanent pasture may be the only sensible option.
Based on this image we can see the importance of effective management of the grass veld to avoid severely degraded areas. Once degraded, drastic measures are required to reclaim the veld
In the sweetveld, reclamation of degraded sweetveld may be a viable option as results can be achieved within a management time frame. In areas with extensive erosion where limited pioneer species are present or little seed in the seedbed available, resting the veld will be a very tedious process. This process may be accelerated by oversowing pioneer grass species or thatching (laying cut grass which is in the seed-bearing stage on bare areas) grass harvested from adjacent areas on degraded areas. Gabions can be constructed to obstruct overland flow to trap silt and provide a medium for seed germination. In the case that a crust has formed, ripping the soil will improve conditions. In other less degraded areas where a sufficient seed bed is available, extended rest periods with lenient stocking pressure will help facilitate sward recovery.
Productivity of the Veld
Productivity of the veld can be expressed as:
- The amount of dry material which can be produced per unit area per unit time which is usually expressed as kg/ha/year;
- The amount of animal production per unit area per unit time.
The first above is regarded as the primary and the second as the secondary production of the veld.