Using fire to maintain grassland

Grass is the cheapest of all livestock feeds – it can even be free.  Good management aims to provide high quality feed for as long as possible thoughout the year. In the tropics, most of the grazing is unfenced (apart from commercial farming animals) and most areas are grazed by animals that have many owners such as in the Masi Mara in Kenya.  This means that a coordinated approach of agreement between all stake holders must exist to implement management and improvement practices. The tools of management are the hoe, cutlass and most importantly, fire.

Using fire as a tool for improving grassland management Burning is a traditional method of managing grassland.  It has been practiced over centuries by the Aboriginals in Australia, native Americans in USA and in the savannahs of India and the Mediterranean. The North West Plains of the USA have introduced burning in the 2000’s to restore the native prarie grasses and to improve the wildlife habitat.  More specifically “grasslands are burned primarily to manipulate vegetation and enhance the biological productivity and diversity of specific organisms or to acomplish specific objectives” (Quotation from Northen Prarie Wildlife Research Centre).

Advantages of burning the grassland:

  • Destroys dry unpaletable grass and enables new paletable shoots to grow
  • Destroys insect pests, parasitic worms and cattle ticks
  • Phosphate in the ash is recycled back as a fertilizer for young shoots

Disadvantages of burning the grassland:

  • Destroys the soil cover and the organic matter and this leads to soil erosion
  • Loss of Nitrogen and Sulphur from the soil

Planned burning needs the use of firebreaks to control the burning stretch, and a technique called back burning if necessary.   Back burning is the setting of small fires along a firebreak and burning back to the main fire front.  The on coming fire should then stop when it reaches the burned area as there is no more fuel to maintain it. Burning should be done either at the beginning or end of the dry season.  The advantage of burning at the beginning of the dry season when the grass is not fully dried out, meant that the fire should not get too hot.  After the fire, trees and grasses shoot again to provide a little grazing in the dry season.  Burning at the end of the dry season, the grass is dried out and the fires get very hot and difficult to control.  This fire can damage shrubs and really scorch the earth. Ideally, grassland should only be fired every other year but unplanned burning happens. Hunters in Nigeria use fire to flush out their prey, and shifting cultivators also burn grassland at their convenience.  Lightening that accompanies the storms when the rainy season is approaching also cause fires.

Other methods of improving natural grazing
Providing that there is some co-operation between livestock owner and herdsmen, other things that can be done to maintain and improve grazing are:-

  • Agree to rest certain areas under rotational grazing
  • Using swamps for dry season grazing
  • Closing cattle tracks to rest them if they are becoming eroded
  • Chopping down undesirable shrubs
  • Constructing dams and boreholes to increase the number of watering points
  • Sowing legumes which are adapted to the area and can tolerate burning and grazing
  • Plant leguminous browsing plants to increase the value of grazings

Fencing
A fence restricts the grazing area and will allow areas to rest.  Wooden fencing does not last very long in the tropics due to termite damage,  Hardwood fencing or treated wood will last longer, but is prohibitively expensive for many farmers. Live fencing is an alternative.  Plants can be laid as hedges which provide an effective barrier as in theUK.

Sown Pastures
Properly managed sown pastures have been successfully done in a few areas of the tropics.  They are high maintenance though requiring fertilizer, spraying and bush cutting which are not normally done by farmers in the tropics.  Also, fertilizer and sprays are expensive.

Fodder Banks
Where grassland is communally owned, it is difficult to plant grasses or sow pastures.  One solution is to plant small areas of land in the wet season which are fenced off until the dry season creating a fodder bank.

Zero Grazing
This is keeping animals in pens or shelters and fodder is cut and bought to them. This controls overgrazing and new grasses can be sown and carefully managed.  It is labour intensive, but does allow more animals to be kept per hectare. Zero grazing is not a natural way of keeping cattle and has been described as cruel by organizations such as PETA (Source PETA.Org).

Written by Fiona Johnson

November 2011

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