The Burning Question
We read every winter in the media about fire destroying the bush or veld in conservation areas such as the Kruger National Park, or on farms. Certainly when a nature reserve manager or a farmer has rested veld during the grazing season with the aim to graze it in the winter, it is a seasonal loss. The veld, however, has not been destroyed.
Fire is very much a part of the ecology of our grasslands and is used as a management tool by conservationists and farmers. Why is this so? In the high rainfall areas of KwaZulu-Natal the vegetation would naturally progress to forest but for fire and, to an extent, grazing. Experimental areas have been demarcated and withdrawn from fire and grazing, and in a matter of years, the initial forest trees become established. In addition it is important for farmers to maintain their veld in a good condition for their cattle. Cattle graze selectively and the unpalatable grasses are not grazed. In time many of the tufts of the palatable grass species become rank and are not grazed. They then become moribund, that is, the leaf matter dies off and in time the crown of the plant becomes a mass of dead material. Then newly emerging leaves are shaded out and the plant weakens. To preserve a healthy grass sward, the grassland must then be burned. It is also a fact that the palatable plants become selectively overgrazed and the unpalatable grasses and weeds can compete successfully and become dominant in the grass sward. In fact the grasslands of the moist areas of the Province are fire-maintained.
While cattle do not perform well on old, unburned grass, from an ecological point of view it is important to maintain a healthy sward. Not only does this reduce the loss of soil, but the biodiversity of the area is improved. In experiments in the grasslands of the Drakensberg, it was found that both the small mammals and grass birds, including game birds, benefited from a burn every second year. In the second year after a burn, these animals were found to be most abundant in the grassland, and their numbers started to decline if the grassland was not burned for three years or more. Then there are many of the veld flowers that depend on fire to provide good growing conditions. The rare Hilton daisy is one of these, and two of the best displays of these beautiful flowers can be seen in fire-breaks that are burned every year. One of these, at Babanango, experiences such hot fires that an adjacent wetland has been destroyed by the annual hot fires burning the organic matter, and yet, alongside this destroyed wetland there is a blaze of red flowers every spring.
In the low rainfall areas (below 750 mm rainfall per year), burning also helps to 'freshen' the grass, but plays an important role in reducing bush encroachment by thorn trees (Acacia species) and other invading plants. In our game reserves the tourist would see little game in a bush-invaded reserve because the visibility would be so restricted. Certainly some games species, such as the browsing kudus do benefit in the early stages of bush encroachment, but the grazers such buffalos would be deprived of grazing areas.
A very important reason for burning is to provide security for homes, crops, timber plantations and animals. Every year devastating, uncontrolled fires sweep over the veld and severe damage to crops and homes results. Firebreaks are burned in the grassland and round homes and crops to protect them against these run-away fires. Yes, fire is a good servant when used under controlled situations, but a dangerous enemy when out of control.