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t
his article is the 19th in a series of articles highlighting a
specific pasture crop species that can play an imperative role
in conservation agriculture (CA) based crop-pasture rotations.
Besides improving the physical, chemical, hydrological and
biological properties of the soil, such species, including annu-
al or perennial cover crops, can successfully be used as animal feed.
Livestock production systems are in many ways dependant on the
utilisation of pasture species, in this case as a pasture cover crop,
and can therefore become an integral component of CA-based
crop-pasture rotations. It is important to identify a pasture species
fulfilling the requirements of a dual purpose crop, i.e. for livestock
fodder and/or soil restoration.
This article focuses on an annual cover crop with enormous pas-
ture crop potential used to improve soil conditions and to provide a
good grazing for ruminants.
Secale cereale L.
(stooling rye/
stoelrog
)
Stooling rye is a tufted annual grass species that can grow as tall
as 1,5 m. Rye has an extensive, fibrous root system that may go as
deep as 1,5 m.
Stooling rye is a valuable fodder (for pasture, hay or silage) and a
cover crop during winter. When it is used as a cover crop in double
cropping systems, stooling rye during late winter/spring provides
valuable forage to animals going into summer.
Of all the cereal crops, stooling rye is the tallest and the hardiest
annual species. There are many cultivars of
Secale cereale
; research
has shown however, that diploid cultivars are more drought-hardy
than tetraploid cultivars.
Agro-ecological distribution
Stooling rye is usually cultivated in areas with cold winters and
warm, dry summers, notably in central, eastern and northern
Europe, though it is also grown in Africa, Asia and North America. It
can grow at very high altitudes and in the tropics it is only found at
high elevations (Brink, 2006).
It grows best at temperatures ranging from 15°C to 20°C; how-
ever, research has shown that this species can tolerate a wider
temperature range (3°C to 31°C). Once well-established, it can with-
stand very cold conditions (down to -35°C).
Stooling rye grows well under 600 mm to 1 000 mm annual rain-
fall and is relatively drought-resistant: It can tolerate dry conditions
with an annual rainfall as low as 400 mm. Rye prefers well-prepar-
ed, fertile, well-drained sandy or loamy soils, with a soil pH ranging
from 5,6 to 6,5.
Because it is tolerant of low temperatures, of droughty conditions
and of dry and acid soils, stooling rye may be cultivated in places
where wheat cannot grow. Rye grows better on light loams and
sandy soils than on heavy clay soils.
Management and utilisation
Stooling rye can be sown with other cereal forages, such as oats,
wheat, or even with annual legumes. Seeding rates can be between
25 kg/ha - 50 kg/ha (dryland) and 50 kg/ha - 75 kg/ha (irrigated)
and depends upon whether it is sown in a mixture or not.
The best time to seed this species is February/March. Stooling
rye forage is also profitable when sown with companion legumes,
such as white and red clover or grazing vetch. The forage sustains
the legume and the association makes full benefit of residual nitro-
gen (N) in the soil (UC SAREP, 2006).
It is a valuable winter feed that helps the livestock producer from
being less reliant on preserved fodder during winter periods. This
species can be grazed late in the autumn and early winter period
and then late winter and early spring.
Stooling rye forage can also be used to make silage and haylage.
It is recommended to harvest rye no later than at early boot stage
(before heading) in order to maintain good palatability, intake and
nutritive value.
When the plant reaches boot stage, the species should yield in the
order of 7 tons - 10 tons of dry matter (DM)/ha under optimal man-
agement conditions. After stooling rye forage is cut, it should be
wilted and then made into silage.
Research has shown that hay making of stooling rye is possible, but
difficult, since forage moisture is too high at the early boot stage
for easy drying.
WAYNE TRUTER,
University of Pretoria,
CHRIS DANNHAUSER,
Grass SA,
HENDRIK SMITH,
Grain SA and
GERRIE TRYTSMAN,
ARC-Animal Production Institute
Integrated crop and pasture-based
livestock production systems
– Part 19
AGRICULTURE
Conservat ion
Series
ON FARM LEVEL
Conservation agriculture
Oktober 2015
62