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These soil nutrient levels are often not economically justifiable if
soils have low levels occur, which justifies the use of Seradella as it
is adapted to low fertility. It is not common to find insect pests, root
or foliar diseases on Seradella plants; however, international reports
have recorded mites and worms occasionally feeding on the plant.
Since Seradella is a legume, its purpose can be either to provide
a protein rich fodder or rather to be incorporated into the soil as
a green manure. If grazed, the recommendation is to do it infre-
quently and with a moderate grazing pressure. Very good hay can be
made from Seradella as long as it is not dried out too much, resulting
in significant leaf loss.
The use of Seradella as a living mulch was investigated in small
scale farming systems in the Eastern Cape and KwaZulu-Natal. With
frequent rainy events in autumn, good yield culminated after inter-
seeding Seradella and Seradella/oats mixtures into maize during late
February. The living roots in the soil had a positive impact on soil
health, supplying food to micro-organisms.
The efficiency of this system needs to be calculated over two or
even three years of practice. The suppression of weeds and insect
pest’s pressure may favour such interventions.
Soil conservation and health benefits
Considering the green manuring benefits of Seradella, it is ad-
visable that this crop be planted on soil prior to winter, and not
necessarily fertilised for maximum production, since this can poten-
tially have an impact on the soil moisture content build-up over the
rainy season.
This species can be planted to additionally provide a soil cover to
limit soil moisture evaporation and wind erosion. Finally, once the
crop has grown to maturity and fixed nitrogen, it can be incorporated
into the soil prior to the following summer’s grain crop.
Management challenges
The most significant management challenge with Seradella is to
ensure that the seed is well inoculated and not planted too deep.
This is sufficient motivation for a nurse crop to be planted along with
Seradella. Another management challenge is the grazing manage-
ment of the species to sustain a good dense stand. If the plant is
overgrazed the stand will become sparse and unproductive resulting
in a higher incidence of unwanted species (weeds).
The most effective method of utilisation is hay or silage making. With
regards to hay making, leaf loss can become a management chal-
lenge if the harvested plant material is dried for too long.
Animal production aspects
As a hay and silage crop, dry matter yields are important and can
vary from anything between 4 tons/ha - 10 tons/ha, all depending
on the inherent soil fertility, moisture and type, in conjunction with
climatic conditions.
Seradella can have a crude protein content as high as 20% - 25%
with a very high digestibility, which declines as the plant matures in
addition to a lower ratio. This very palatable species can
even provide a metabolisable energy (ME) value of 10 - 11,5 MJ/kg.
Conclusion
Seradella is not a well-known legume crop in South Africa, however
it has many benefits that can support and play an integral role in con-
servation agriculture. If managed correctly, it can be a persistent and
vigorous grower with good palatability and nutritive value.
It also has a good tolerance for poor soils, but should rather be seen
for its potential as an interim crop (green manure) between a long-
term pasture ley crop and the next annual grain crop. Its drought-
tolerance and adaptation to poor growing conditions makes it a
suitable candidate as a green manure crop.
For more information, contact Dr Wayne Truter at wayne.trut-
Prof Chris Dannhauser at
Dr Hendrik Smith at or Mr Gerrie
Trytsman at
1: Yellow Seradella in bloom.
2: A French (pink) Seradella flower.
ON FARM LEVEL Conservation agriculture
CONSERVATION AGRICULTURE
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