Tropical storm Eloise that recently hit South Africa and caused widespread flooding continues to pose a risk to crop and livestock farmers in parts of Limpopo and Mpumalanga.
According to the Agricultural Research Council’s agro-climate network, local flooding brought on by Eloise, which first made landfall in Mozambique on 23 January 2021, now threatens Mzansi’s summer grain crops.
The ARC expects more than 150mm additional rainfall over the western parts of the summer grain production region in early February. This is a critical period of the growing season for these crops.
persistent wet conditions could also CAUSE diseases in animals.
Meanwhile the South African Weather Service has issued an “orange” warning of disruptive rainfall for these regions. Flooding is possible in low-lying areas. Earth dams are also expected to give way in some areas.
This ultimately means that crop and livestock farmers will have to grin and bear the potentially devastating weather conditions for a little while longer.
However, the ARC offers advice for farmers to limit crop damage and the impact on livestock amid the expected high rain season.
How to mitigate crop damage
Farmers in affected areas are recommended to monitor nearby streams and rivers, as there could be further flash flooding with sudden rising water levels due to rain in the catchment area.
There is a way, however, to mitigate this. Farmers could open some drainage furrows at the edge of the lower parts of their fields to facilitate quicker drainage of surface runoff water, according to the ARC.
In February, crop farmers have little opportunity to replant. However, the ARC says, if some fields have well-drained soils, there is perhaps a window of opportunity to plant a short-season crop. These include sunflowers, beans and other legumes or vegetables that can be harvested before the first frost.
Meanwhile the remainder of the summer rainfall region is also expected to receive further rain, with maximum temperatures somewhat lower than normal, resulting in decreased evapotranspiration rates. This means that less water will be able to evaporate from the soil, leaving it sodden.
Luckily, this will be of benefit to summer crops by providing increased soil water in the profile for the next few weeks, the ARC states.
Are your livestock pastures under water?
Due to the higher rainfall in the wet season, with more rains still expected, many farmers, their pastures and livestock are under huge pressure.
These pressures, according to Dr Klaas-Jan Leeuw, an ARC researcher specialising in beef cattle nutrition, are starting to be felt in the feeding of livestock and the condition of the pastures.
“Where there is little ground cover, the topsoil and the seeds in it can be washed away by heavy rainfall, leading to a loss for the farmers as the pasture can carry less livestock,” he explains.
Also, opportunistic weeds such as the pom-pom weed and bankrupt bush can establish themselves easily, further reducing carrying capacity.
Leeuw says while pastures with full or close to full ground cover can deal with large amounts of rain, on overgrazed pastures and pastures with moderate ground cover, opportunistic weeds may still flourish.
In addition, the wetter soil makes for deeper hoof imprints. If that is done by a large number of livestock over a longer period, Leeuw says, it creates a muddy area that will take longer to rehabilitate.
“The best way to deal with this is by moving the feeding and water through more frequently, if possible. If the farm has sufficient camps, do move the cattle more frequently, this may reduce mud pools forming in the camps,” he says.
Livestock owners are also advised by the ARC to move their large and small stock to high-lying drier areas to prevent possible foot rot infections.
Furthermore, the expected persistent wet conditions, they say could also result in the occurrence of fungal pathogens, which causes diseases in animals.