Whether damaged through a bush fire or bovine overgrazing, the veld supporting southern Africa’s game farms and reserves can be assisted to return to its natural glory and intended carrying-capacity. Evirogrow’s Mike Zingel explains to freelance writer Alistair Cotton how the Madikwe East Private Game Reserve was effectively rehabilitated after a fire destroyed 80 hectares of veld.
Flashing lighting as a signal to the end of winter, an angry afternoon thunder-storm rolls ominously over thick, tinder dry grass and parched native trees. Like a giant magistrate slamming his gavel, the cloud unleashes its electric judgment on the land below.
Umlilo! Fire! Only fear shares a common language.
In minutes the flames tower above blazing trees, leaping roads, rivers and inadequate fire-breaks. The men from the farm have gathered to launch a counter-offensive. The neighbour, his team and “fire fighter” bakkie are on the way.
The men, armed with whatever they can find – black rubber mats, wet sacks and even branches – fight back.
All night they toil, seemingly pointlessly, against the overwhelming power of the raging bush fire. But at three in the morning the wind subsides and by five the fire is burning itself out on a rocky koppie.
Exhausted, the land owner walks back over the battle-ground where smoldering charred stumps smoke where proud acacia once grew.
“The devastating effect of a bush fire on a natural reserve can be severe and have tragic consequences,” say’s Envirogrow’s Mike Zingel. ” In a natural environment, grazing and browsing species would move away to areas not affected by a bush fire – giving the land precious time to recover naturally. Since fencing has put a stop to this natural process and too many of our reserves and game farms are overstocked, a large bush fire can have a catastrophic impact on the local ecosystem,” he explains.
Zingel describes the damage which was caused when a serious fire broke out on Madikwe East Private Game Reserve in October 2006. The fire burnt out 80 hectares of veld, grass cover was completely destroyed and the trees which were not killed were severely damaged. The reserve, located in the Limpopo Province 30 kilometres from Derdepoort on the Botswana border, could have been severely impacted by the blaze.
However, Poon Liebenberg, the owner of the 5 700 hectare reserve and his manager George Child, worked out a masterful rehabilitation plan which dramatically assisted the veld to rehabilitate after the fire. Rehabilitation was started in the summer of 2006 and carried on right through the winter of 2007.
First off, terrain which was most vulnerable to erosion received priority treatment. Trees which take time to replace were at the top of the list from a vegetation point of view.
A strategy to restore grazing, without it being destroyed by the very game for which it was required to support, was carefully devised. In addition, Poon and George took stock of the existing resources so that they could work from a position of strength and limit the cost of outsourced inputs.
The state of the seed bank in the soil, the source of new grass cover, and the importance of saving those trees which had potential to recover, immediately sprang to mind. Zingel comments that the generally flat terrain and deep soils of a large part of the burned out area facilitated mechanical operations for rehabilitation. In addition, the team recognised that the modest game stocking levels of the reserve assisted rehabilitation.
Grass in this extensive area was totally destroyed by a hot veld fire in spring 2007 and trees were either killed or severely damaged. The site is typical of the areas which were lightly harrowed and sown with rehabilitation veld seed mixture without brush packing which was conditional on the whole area being sown at the same time.
There were snags and unknowns too. On the rest of the burned out area, steep slopes and rocky obstructions in the soil were problems that would call for special care. It was not known how much of the seed bank of the veld grass had been damaged in the top soil by the hot fire – a question that could only be answered by time. In addition, most trees in wooded areas where the fire had been particularly intense had been completely destroyed and had to be replanted.
The team lightly disked large tracts of fairly open veld on flat to rolling terrain and seeded with Biomosome sweet and mixed bushveld reclamation veld seed mixture. Fortunately, the whole area could be seeded, as there were few obstructions and consequently they could hope to succeed without incurring the additional expense and labour of brush packing to protect young grass.
Areas featuring steep, sloping terrain with rocky soil which had had its cover burned off was at high risk of being eroded by the summer rains. As mechanical cultivation was out of the question, this soil was loosened by hand hoe and seeded with Biomosome sweet and mixed bushveld reclamation veld seed mixture and lightly raked. Wherever there were clear tracts of soil between the rocks, lengths of metre-wide Soil-Saver hessian matting were laid, fastened-down with roughly hewn pegs made from burnt trees and then brush packed one metre thick.
The team also treated the burned parts of trees with survival potential by spraying insecticide to control wood borers. Where trees been completely wiped out, new recruitments of maroela and tamboti trees were planted in informal clumps and fenced off from browsers.
In August 2008, Zingel visited the reserve to measure how successful their rehabilitation efforts had proved to be. “It was interesting to observe the veld alongside the seeded areas. Here the veld had to recover with whatever the natural seed bank could provide after the impact of the heat from the fire,” Zingel explains. “The seed bank on the reserve is generally good despite the fact that the veld was overgrazed and heavily encroached by bush when the land was converted from stock farming into a game operation.
“Since then, twenty five percent of the reserve has been cleared of excessive bush. Over the past decade hot fires on ten percent of the area have contributed to opening-up the veld. Thanks to conservative stocking with game the grass component of the veld has been allowed to recover for the past five years and the composition of the veld has improved dramatically on most parts of the reserve. Increaser grass species associated with overgrazing have been overtaken by palatable perennial grasses. In the process, the seed bank has been replenished with grass seed of desirable species,” he says.
Never-the-less, observation showed that there was a clear advantage in the seeded area over the neighbouring unseeded veld in terms of cover and mass of grazing.
“The trees which had survived and had been treated with insecticide were regrowing with negligible wood borer damage, destined to become gnarled beauties characteristic of the bushveld. Since the fire, in areas where mature trees had been destroyed, they have made individual cages with wire mesh supported by fencing standards to protect surviving young trees which they found ratooning in the veld. These survivors are a valuable adjunct to the new recruitments of maroela and tamboti trees now growing well in the fenced off areas,” he continues.
The most demanding rehabilitation was in the steep and rocky areas. There were odd showers during the laying down period, which caused some germination, but the big rains of summer 2007 and 2008 were decisive and resulted in the establishment of excellent grass. Brush packing with thorn branches allowed the grasses to flower and go to seed without interference of grazing animals.
Steep slopes and aspect were both threats to reclamation. Above is without a steep slope, therefore there was no great threat and no seeding or covering was done. Below, the slope becomes increasingly steep to the right, the aspect is northerly and seeding was indeed necessary.
“Brush packing in this style proved a very important contributor to erosion control. It is an obstruction to excess water running down slope after rain. By slowing flood water it allowed the soil being carried down to sink and collect against the branches. The deposit of soil contributes well to seed bed development in the veld.
“Brush packed 500mm to one metre thick will allow grass which germinates under its cover to develop fully, flower and go to seed. Development is important, as grass cover itself is a natural obstacle to erosion. Flowering and going to seed means that seed, which is difficult to plant in sloping rocky terrain is being produced on a large scale, resulting in more seed than could readily be afforded if it were to be purchased. This seeding is very important to rehabilitation of inaccessible places. It is also a deposit in the seed bank for the future,” Zingel explains.
It was clear that the grass in the large tracts of land that were mechanically prepared and seeded was well established. Although the rainfall of the summer of 2006 and 2007 was below expectation there was sufficient establishment and growth for successful survival of the first season plants. Excellent rains of the past summer caused further germination of grass seed, development of the survivors of the previous season and brought the project to a happy conclusion.
The necessity of planting unprotected areas all at the same time and the importance of these areas being large relative to the game count can be shown in the impact of blue wildebeest on one of these tracts on the reserve. “Now, two years later blue wildebeest grazing lawns can be seen as short grazed patches occurring randomly over the area. This kind of grazing habit had not had any real impact on the grass in the early stages. It was a case of safety in numbers,” says Zingel.
Poon Liebenberg, proprietor of Madikwe East Private Game Reserve on one of the wildebeest grazing lawns that occur from place to place in this area. Grass rehabilitation in this large area after the fire October 2006 was well under way before the game could graze it out.
There are many impacts on veld which call for rehabilitation. Fire is just one. However the principles involved in successful rehabilitation are the same regardless of the cause.
The experience of successful rehabilitation on Madikwe East Private Game Reserve goes to show how important it is to work out an appropriate rehabilitation strategy, making the best of the advantages of existing resources. Where inputs were necessary budgeting of total cost, which included the collection, transport and placement of thorn brush, application of Soil-saver and purchase of appropriate seed was done before work started. Poon and George proved that when planting veld grass seed it is vital to apply strategies and techniques that will result in the plants reaching maturity, flowering and producing further seed.
For more information on how to go about accessing the status and carrying capacity of a game farm or reserve, effective seeding mixtures and procedures and how to assist natural veld rehabilitation, please call Mike Zingel on 083-252-1834 or email firstname.lastname@example.org
This article is also available as a .pdf download as it appeared in the magazine in Afrikaans.