24 March 2024
It’s not only summer grain farmers who have suffered significant damage due to the unfavourable weather conditions this summer. Extensive livestock farming, especially in central and western parts of South Africa, is experiencing significant risks.
The damage to summer crops caused by heatwaves and drought conditions is largely irreparable because plantings are already well into the growth cycle in many cases. “Even very late plantings have sadly grown poorly due to the scorching heat,” says Johan van den Berg, an independent agricultural scientist.
The other industry facing significant risks is extensive livestock farming, especially in central, western and southern parts of the country. The growth period of grassland pastures is mainly from December to February in eastern parts. Then, minimum temperatures are still high enough for growth (above 10°C). The growth period across the central parts is January to March, and from March to May across the western parts of the country, when maximum temperatures are lower.
“The most important growth period for Karoo bushveld is from March to May. Fairly good pasture production can also occur from March to May in the warmer northern Bushveld. Therefore, rain as soon as possible is extremely important in the latter areas,” explains Van den Berg.
Lower minimum temperatures
Although daytime temperatures are still high, nighttime temperatures have started to sharply decline, especially in central, southeastern and eastern parts. At Reddersburg, Smithfield and Zastron in the southern Free State, minimum temperatures below 10°C were recorded on 16-18 February, 5-10 March and 15-17 March. Light frost has even occurred as early as 16 February. In February and March, minimum temperatures also dropped sharply in the Eastern Cape. “These cooler periods have been long enough to significantly weaken the growth of grassland pastures,” says Van den Berg.
Although rain is always welcome, the grasslands of the Kalahari, the bushveld of the Karoo and the Bushveld grasslands in the northern parts of the country are the only grazing areas that will truly benefit from rain before June.
Good management vital
From a management perspective, rain and consequently pasture production in the second part of the summer will be extremely important. This determines the quantity and quality of grazing for winter, spring, and often the first part of summer.
“Since rainfall patterns have begun to change over the past two decades – winter, spring and early summer rains in the summer rainfall region are decreasing – there are red lights flickering for the coming months,” says Van den Berg. “There’s a saying among livestock farmers that the winter months until August are the ‘thin months’, but that September and especially October are the ‘killing months’.”
Reproductive livestock, with calves or lambs that need high-quality nutrition, can struggle significantly. “Livestock that calved or lambed too early in the summer before it rained and when there was sufficient grazing, are particularly in trouble.”
The trend of weaker winter, spring and early summer rains, but more rain in midsummer, leads to a shorter grazing production season that is difficult to manage, especially for the reproduction of large livestock. If the calving season is too late, it results in too short a growth period for calves to reach a marketable weight before winter.
Van den Berg encourages farmers to sharpen their pencils around their livestock and grazing planning in the coming months.
Late winter rain
Van den Berg says an El Niño system is traditionally responsible for above-average rainfall for the winter rainfall region. However, this is valid when strong El Niño-like conditions occur during the rainy season from May to September. “During the weakening phase of an El Niño system, and especially the transition phase to neutral or a La Niña system, conditions for rain can be below average.”
Another trend is that the winter rainfall season may start late during the transition phase.
“In almost all of these similar years, there has been at least one month, namely June, where fairly average to above-average rainfall occurred, with July tending towards average. What is worrying is that the September months during similar years also tended towards average to below-average rainfall.
“Winter grain production conditions may therefore tend towards average to below average.”
Risk for dams
Van den Berg says a major risk of the expected conditions is a lack of rain for dam replenishment. Although dam levels in the Western Cape are still fairly good, and 10% to 15% better than in the corresponding period last year, this may indicate a turning point towards less water in dams for the coming seasons.
“With the very high temperatures of the past months, dam levels decrease very quickly. Evaporation and consumption should, however, decrease rapidly from the second week of April with cooler conditions expected.”
