Marginal drylands are seldom economically viable for the production of commercial crops. The value of these lands is between that of natural veld and medium- to high-potential drylands. However, the age and condition of the plants, weed infestation and other value-inhibiting factors must be considered. The suitability of the cultivar for the area is also important.
A useful alternative is to establish permanent pastures, either on dryland or under irrigation. They may consist of grass, broadleaf plants, a mixture of grasses, or a mixture of grass and broadleaf plants.When deciding which permanent pasture to establish, consider the following factors:
- Annual rainfall, rain distribution between winter and summer, and rainfall intensity;
- The pasture’s sensitivity to low temperatures and frost;
- The pasture’s adaptability to sandy, clay or organic rich soil;
- The pasture’s function – whether it will be baled, used as standing hay, or used as green pasture.
Perennial Dryland pastures
The value of a dryland permanent pasture is normally between that of grazing and arable land in the area. Properly treated and fertilised pastures may significantly enhance a farm’s carrying capacity. Research conducted at North-West University established that pastures planted on dryland can increase meat production per hectare by three to four times more than natural veld in the same area.
The following are popular dryland perennial pastures in South Africa:
- Eragrostis curvula (weeping lovegrass/oulandsgras)
- Endemic to South Africa, this is the most commonly planted pasture for grazing and haymaking. It is well-adapted to summer rainfall areas with rainfall exceeding 650mm/annum, but will survive with a minimum rainfall of 450mm/ annum. Yield is between 8t/ha and 20t/ha.
Digitaria eriantha (Smuts finger grass)
Regarded as one of the best grazing grasses, this is often used as standing hay, as it remains tasty until late winter. It is not used for haymaking, as it does not dry out easily. It can grow in areas with rainfall of 300mm/annum, but, as a planted pasture, it does best in areas with rainfall exceeding 450mm/annum, where it can be grazed at 5LSU/ha to 6LSU/ha (large stock unit/ha).
Cencrus ciliaris (foxtail buffalo grass/bloubuffelsgras)
Endemic to Africa, this grass can be planted in areas receiving rainfall below 300mm/ annum, but its production is negatively influenced by cold conditions. It grows better in sandy to sandy-loam soil and is difficult to establish in clay soils. It is hardy in dry conditions and has a root system up to 2m deep. A tasty grazing grass, it produces a high yield.
Irrigated perennial pastures
The value of irrigated permanent pastures normally consists of the value of the irrigated land plus the depreciated value of the establishment cost. Planted pastures under irrigation are used mainly in intensive farming, such as dairy farming, or for haymaking. The country’s most commonly planted irrigated pastures are probably lucerne and kikuyu grass.
Medicago sativa (lucerne)
Called the ‘king of haymaking’, lucerne can be established in areas with rainfall of at least 400mm/annum, but performs best under irrigation. With its 3m-deep root system, it prefers deep soils. It can give between four and 10 cuttings per season, producing between 15t/ ha and 20t/ ha or more, depending on the moisture and climate. The most popular cultivar is SA Standard.
Pennisetum clandestinum (Kikuyu grass)
Originating in Kenya’s Kikuyu region (Dannhauser, 1987), this is a creeping grass and a prolific grower able to withstand heavy grazing. For optimal production, rainfall must exceed 700mm/ annum. If this is not the case, it must be irrigated. It grows best in loamy or clay soils. Kikuyu is primarily a grass suited for grazing and not haymaking. It is popular with dairy farmers, especially along the coast.
Rumpff Krüger (BCom [Hons] in Economics) is the owner of ACOM Valuers (Pty) Ltd, which specialises in the valuation of agricultural properties.