1 INTRODUCTION – VELD MANGEMENT
The term veld is a Southern African term for natural vegetation, utilized by livestock. In other parts of the world it is called rangelands.
Veld includes different plant types like trees, shrubs and grasses. The trees and shrubs produce fodder (leaves) mainly for our game animals, as well as goats. These leaf eaters are called browsers. The grass is utilized by livestock like beef cattle, dairy cattle, sheep, horses and donkeys. They are the grazers (grass eaters).
1.2 More about the grass plant
The grasses are some of the most important plant types, because they supply different forms of food to humans and animals. Maize, sorghum, wheat, oats, rice, sugarcane are all part of the grass family which are used by humans. Veld grasses and planted pastures supply grazing to animals that produce meat, milk and wool to us. Another very important role of grasses is controlling soil erosion, thus they are soil protectors.
To supply enough meat, milk and wool the animals and the veld should be managed well. From there the old statement: “A farmer can only be a good livestock farmer if he is a good grass farmer”
Gibbs Russell (1985) mentioned that there are 967 different grass types (also called grass species) in Southern Africa.
The following information seems to be very scientific, but to manage our veld well, we have to take notice of it. Veld grasses are classified in different ways, for example palatability of different species and the role that they play in the veld condition or productivity.
1.2.1 Palatability of grasses
There are three main groups of veld grasses:
- Grasses that are highly palatable, those that are preferred by grazing animals
- Medium palatable grasses, those that animals utilized when the highly palatable ones are finished.
- Unpalatable grasses are those not preferred by grazing animals, but if there is nothing else they will graze it and lose weight.
The palatability and grazing value of grasses are normally evaluated in the laboratory in terms of the protein content and the fibre content as indicated in Table 1. These chemical values are very valuable to use, because the Protein in animal feed, and also in human food, is important for growth and good body condition. The fibre is the hard or tough component of the food that makes it less digestible.
Table 1: The influence of protein and fibre in grass quality
|Quality||Crude Protein (CP) (%)||Fiber (%)|
|Good quality||Above 18%||30% and lower|
|Medium quality||11 – 18%||30 – 35%|
|Poor quality||10% and lower||Above 35%|
It is important to remember that if the CP content of the pasture or grass is above 13% the animals can only maintain their weight and above 18% they will gain weight. When the CP content falls below 6-8% the palatability will be low and the pasture intake by the animal will be less and they will lose weight. Palatable and good quality grass will have a fibre content of less than 30%. If above 35% it will become unpalatable, animals will take in less grass and will lose weight
It is not always possible to take grass to the laboratory. However the breaking strength of the grass leaf is an indication of the fibre content of the plant. If you pull and break leafs of different grass species, as shown in Figure 1, you will feel differences between grasses.
The easier it breaks, the less fibre and more acceptable to the animal. If tough and not easy to break it is high in fibre, not acceptable to the animal. It is important to do it in a green, active growing stage.
In Table 2 the grazing value or acceptability of the more important grasses in the grassland of the Free State, North West, Gauteng, Mpumalanga and KZN is given on a scale of 0 to 10, as explained below.
0-1 not palatable, fibrous with a low grazing value,
8-9 highly palatable and,
10 highly palatable and utilized throughout the season
Table 2: The Grazing value (Palatability) of the more importantgrass species in the Highveld grassland.
|GRASS COMMON NAMES||BOTANICAL NAMES||Grazing value|
|Red grass Turpentine grass||Themeda triandra Cymbogon plurinoides||7-8 1|
|Finger grass Creep buffalo grass Thatch grass Kweek/Couch Weeping love grass Curly leaf||Digitaria eriantha Panicum coloratum Hyparrhenia hirta Cynodon dactylon Eragrostis curvula Eragrostis rigidior||6 7 4 4 3 1|
|Natal Red Top Three awn grass||Melinus repens Aristida spp||1 0|
1.2.2 Veld condition. The condition of the veld is also an important norm to evaluate the potential animal production on the farm. If soil is severely over grazed with bare patches (photo bellow left) or if it is totally without grass, like the photo below on the right hand side, we know that there is not enough grass for the animals and erosion can starts with the first rain.
Luckily in our nature there are plants that will start to grow there. Some of them will be weeds, but there are also annual and perennial grasses. This development from bare soil to a grass covered stage is called succession and it happened over time in three different stages. These stages can be identified by different grass species.
- Pioneer stage– The species that germinate first on disturbed or bare soil are called pioneers. They are mostly annual species, drought resistant, with different levels of palatability.
- Sub climax stage – Bi-annual or perennial species that follow the pioneer species a year or three later are sub climax species. Some of them are palatable
- Climax stage – Perennial species that establish later in the development process are climax species. Most of them are palatable and the best fodder plants, but there are also unpalatable ones.
This process can also happened in the opposite direction, from climax to pioneer stage if the veld is over stocked and over grazed. Table 2 shows the different grasses that will grow in the different succession stages.
Table 2: The important grass species that grow in the different succession stages in the Highveld grassland.
|GRASS COMMON NAMES||BOTANICAL NAMES||SUCCESS STAGE|
|Red grass Turpentine grass||Themeda triandra Cymbogon plurinoides||Climax Veld|
|Finger grass Creep buffalo grass Thatch grass Kweek/Couch Weeping love grass Curly leaf||Digitaria eriantha Panicum coloratum Hyparrhenia hirta Cynodon dactylon Eragrostis curvula Eragrostis rigidior||Sub- climax / Late pioneer veld|
|Natal Red Top Three awn grass||Melinus repens Aristida spp||Early pioneer veld|
If the veld is in the pioneer stage (over grazed) our management should be aimed to improve it to the climax stage. If the veld is in a good condition our aim should be to keep it like that (in the climax stage) with good management.
The afore mentioned information, is Part 1 of a series of articles and it was a description of some of the more important grazing and indicator grass species on the Highveld grassland. In the articles that will follow more detail will be given on:
- The interaction between the grazing and rest of the grass plant and how that effects veld condition.
- The influence of climate change rainfall on the veld
- Grazing management systems
- The contribution of planted pastures to animal production
Prof Chris S Dannhauser
Sel no (+27) 082 873 4736