livestock units (MLU)/ha with a live weight gain of 490 kg/ha. With
regards to sheep production systems, 20 - 25 sheep/ha can be eco-
nomically viable.
Grain crop production
After establishing a typical ley crop system using tall fescue for a
period of around three to five years, the soil should be sufficiently
restored to cultivate annual grain crops under aCA system.
Herbicides kill the pasture quickly and the pasture residues remain
on thesoil surfaceprovidingcover that limitserosion, enhancewater
infiltration and reduces their rate of mineralisation. Once a decision
ismade to terminate the ley, all pasture components shouldbe con-
sidered as “weeds” that need tobe removed. They shouldno longer
be regarded as a sourceof fodder for livestock.
In certain situations/areas, an annual legume could be planted di-
rectly after termination of the ley crop, such as grazing vetch (
Vicia-
villosa
) as awinter cropor cowpeas (
Vicnaunguiculata
) and soybean
(
Glycinemax
) in the followingsummer, followedbymaize (
Zeamays
)
in the crop rotation.
Thewater requirement of the first cropplanned after pasturewill in-
fluence the timing of removal of the pasture, especially in the dryer,
westerngrainproduction regionsof SouthAfrica. Reliable and time-
ly seasonal rainfall forecasts may assist in this planning. Following
thepasturephase, grain cropyield indryer regionswill be restricted
unless the soil water profile is replenished.
After removing the pasture, weeds in the fallowmust be controlled
to conserve soil water tomaximise the benefit of the ley. A suitable
no-till planter shouldbeused toplant thegraincropsdirectly into the
residues of the pasture crop, without any other cultivation practice
disturbing the soil.
Normal integrated fertiliser (based on soil fertility levels and yield
targets), weed and pest control practices should be followed. Dur-
ing the transformationphase after newly establishedCAgrain fields
(e.g. during the first few years after terminationof a ley crop), a 30%
increase inN fertilisers is recommendedonmaize due to the immo-
bilisationof N in the soil.
Thereafter the availability of N to the plant should be assessed
through an appropriate analysis and the fertiliser application should
be adjusted accordingly.
Conclusion
Ina fodder flowprogrammeof ananimal production system, tall fes-
cue is regarded a very important pasture, as it fills the gaps of pas-
ture demand at times when sub-tropical pastures are not growing
optimallyor not having thebest quality.
Themajor requirement however, is that this speciesneeds sufficient
water and ifwater is limited, this specieswill not growwell and isnot
the most suitable species for a livestock production system. When
situated inawinter rainfall or all year round rainfall region, thenwith-
out a doubt this species can be used with much success with the
correct grazingmanagement strategy.
For more information, contact Dr Wayne Truter at
wayne.truter@
up.ac.za
, Prof Chris Dannhauser at
Dr Hen-
drik Smith at
orMr Gerrie Trytsman at
