Sasa has worked with commercial and small-scale growers to promote soil and water conservation, variety improvement, soil health and the management of pests and diseases, which cost the industry R19-million to R20-million a year for research and development.
Incorporating these initiatives in daily farming operations has shown that farming on slopes can have a minimal impact on natural resources.
Sasa extension officer for the Sezela region Dirk McElligott told journalists on a recent media tour that strip planting and harvesting helped prevent soil erosion by retaining moisture and that the trash blanket left after green harvesting reduced the amount of chemical fertiliser farmers needed to use and also decreased the amount of compaction from machinery.
“We also encourage farmers to plant a green legume crop after harvesting to allow the soil to rest, and encourage the local community to grow dry beans,” McElligott said.
In the 9- to 12-month rest between crops, the fields are rid of all noxious weeds and the soil is able to recover.
McElligott said the siting of roads, especially major extraction roads, was a fairly precise science. Water also had to be channelled to a controlled spill point.
In the scientific management of farms, the slope of the land decides the interval of terraces and varieties are changed regularly because yields decline from the old roots. In some places, oxen are still used to plough the fields to ensure minimum disturbance of the soil.
Illovo’s Sezela farm has practised green cane harvesting for the last five seasons and a recent study has shown that yields have increased as a result.
While green cane harvesting is more labour intensive, and, therefore, more costly, the indirect cash benefits in the form of improved weed control, nutrient replacement and soil moisture enhance- ment far outweigh increased harvesting costs.
The study also showed that, compared with growers who burn cane at harvesting, those who only trash experience an aver- age yield increase of about 15 t/ha of cane.
Several challenges remain, including resistance from cane cutters, who often light the cane themselves, starting fires that get out of control. Illovo believes that the benefits of trashing can be further enhanced through ongoing cane cutter training and good management. However, burning cane still remains a good management tool to deal with cane that has fallen over, to prepare fields for replanting, to deal with pests and diseases and to better manage the crop where it is grown in wet, cold valley bottoms.
