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drives soil health. Soil health is the primary factor that has an impact
on pasture herbage quality and subsequently animal health and pro-
duction (Truter et al., 2015).
If a proper ultra-high stock density grazing system is sustained
over time, soil health improvement could significantly escalate, in-
fluenced by positive changes in a wide spectrum of soil parameters,
such as microbes, macro-fauna (e.g. earthworms), C:N ratio, hu-
mus, structure, nutrient cycling, fertility, water infiltration and water
holding capacity, which then result in improved productivity and
profitability of crop-livestock systems.
Stocking rate vs stock density
Stocking rate means the number of animals on a farm for a period
of a year, while stock density refers to the number of animals on
a hectare of land at a specific time. The higher the stock density,
the higher the amount of forage getting trampled onto the soil sur-
face. Ideally up to 50% should be trampled onto the soil surface.
Most producers will call this a waste, but in a CA system this portion
feeds into soil organic matter that triggers beneficial soil biological
processes influencing soil health. So the higher the stock density
the more quickly such beneficial processes could start.
The grazing area
A simple rule of thumb is that a grazing animal will need to eat 3%
of its live weight each day. So, a 500 kg cow will need to consume
15 kg of dry matter (DM) on a daily basis. If 50% of grass is used by
the animals, a camp with a total amount of 4,8 t/ha DM can sustain
160 cows for one day.
During wet spells the herd impact on soil compaction can be less-
ened with additional camps being opened or cattle can be moved
to a rocky part of the farm. If cover crops outgrow cattle demand,
forage can be baled as a last option, but crops such as sweet
sorghum make excellent standing hay that can be used during the
winter months.
With the use of electric fencing a passage can be created which
will allow cattle to reach water troughs in front of or further behind
them without going across ungrazed or recovering grass.
Conclusion
Well-planned and well-executed ultra-high stock density grazing
of annual and perennial ley crop pastures within annual cropping
systems will dramatically increase soil health, leading to improved
productivity and profitability, hence the long-term sustainability of
such integrated crop- and pasture-based systems. For these rea-
sons, such systems are highly suited to rehabilitated degraded soils
and revive declining crop-livestock systems in South Africa.
For more information contact Dr Wayne Truter at wayne.truter@
up.ac.za, Mr Lindeque du Toit Dr Hendrik
Smith at Mr Gerrie Trytsman at
or Mr André Lund at andreenmartie@
gmail.com.
Literature
Chapman, T. 2012. Are mob-grazed cattle the perfect arable break? A Nuffield
Farming Scholarship Trust Report.
Lund, A. 2015. The Karoo grazing experiment 2003 - 2012. No Till Conference 2015:
Drakensville, KwaZulu-Natal.
Teague, R, Provenza, F, Kreuter, U, Steffens, T and Barnes, M. 2014. Multi-paddock
grazing on rangelands: Why the perceptual dichotomy between research results
and rancher experience?Journal of Environmental Management 128, 699 - 717.
Truter, WF, Dannhauser, CS, Smith, H and Trytsman, G. 2014 - 2016. Integrated crop
and pasture-based livestock production systems. SA Graan/Grain.
Truter, WF, Botha, PR, Dannhauser, CS, Maasdorp, BV, Miles, N, Smith A, Snyman
HA, Tainton NM. 2015. Southern African pasture and forage science entering the
21st century: past to present. African Journal of Range & Forage Science, 32(2):
73 - 89.
3: Winter ley crop mix of oats, radish, vetch and tulip at the farm
Skulpspruit. Photo: Hendrik Smith
4: Summer ley crop mix grazed in winter months at the farm
Skulpspruit. Photo: Hendrik Smith
5: At least 50% of crop residues should be left on soil surface after
grazing event. Photo: Jurie Bezuidenhout, Doornbult, Migdol
6: Mobile electric fences are used to move many animals in small
camps over short periods. Photo: Jurie Bezuidenhout
5 6