dc.description.abstract | The study was conducted at Kabete in KiambuDistrict. This is one of the high potential
areas in the central highlands of Kenya where population pressure on land is encountered.
Smallholder mixed farming systems typically involving multiple annual food crops,
animals, fodders and horticultural crops are the norm, with both crops and livestock
components closely integrated. Due to continued cultivation, long fallow periods critical
for soil fertility regeneration are not feasible. In some particular cases the smallholders
are placed in areas with poor terrain and low soil fertility.
In such intensive systems of production, strategies of production that sustain adequate
crop yields and ensure high productivity of livestock have evolved. The development 01-
zero-grazing enterprises where animals are kept inside buildings and fed on harvested
forage and crop residues in cut-and-carry systems has been adopted. However, the
success of zero-grazing milk production has solely relied upon Napier grass tPennisetum
purpurcunn . Napier grass though outstanding in its ability to remain green during the dr~
season, has huge labour requirements for vegetative establishment and weed control ~IS
well as problems of eradication. Unless Napier is properly chopped and fed in adequate
troughs, wastage during feeding is high; moreover, the yield of mature Napier grass is
largely composed of inedible stem. For highly productive milk animals supplementation
of feeel would be necessary; however, most protein ration formulations are expensive t'J
purchase. The use of other potential fodder grasses and legumes is thus warranted.
Integration of forage legumes into cropping and fallow systems IS considered an
attractive option for arresting environmental degradation. The legumes do not only
, ,
contribute to sustaining soil fertility but also provide better quality feed for livestock. The
wide OCCUITenceand forage potential of indigenous (native) legumes in the highlands of
east Africa has been confirmed by various agronomic studies. Some annual native types,
specifically Trifolium quartinianutn cv. Mealton 5 and Trifolium stcudneri have high dry
matter production under cultivated conditions. Their adaptability to local conditions and
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annual growth characteristics could be used to advantage in the intensive farming
systems. The exotic species that have shown promise (e.g. Alfalfa, Siratro and
Desrnodiums) are perennial in growth; they thus cannot be easily integrated into and/or
eradicated from existing cropping systems when not required. Secondly, problems of 10\\'
commercial seed and resultant high seed prices are encountered.
In this study, Trifolium quartinianum cv. Mealton 5 and Trifolium stetulneri were grown
alone, and inter-cr?pped with two grass species, Sudan grass (Sorghum sudanensei and
finger millet tEleusine coracana L.) on a contrasting terrain. The upland terrain had
Nitosols while the bottomland had Vertisols, The potential for dry matter (DM)
production by sale and intercrops under rain-fed and watered conditions was assessed at
90, 105 and 120 days after sowing (DAS). Crude protein (% CP) determinations for the
crop/forage grasses, legumes and their mixes were done.
Both in the long and short rains seasons, the cropping system, watering regime and their
interaction had a signi ficant (p </= 0.05) effect on dry matter yields of the clovers and
crop/forage grasses. Mean dry matter (DM) production by sole T. quartinianunt cv.
Mealton 5 were 3.21 and 3,19 tons/ha in the long and short rains respectively while those
of T. st etulneri were 1.98 and 2.67 tons/ha. The yields in intercrop with Sudan grass and
finger millet were only 30-50 % of those obtained under sole cropping. Overall DM
yields for intercrops were higher than sole clover but not sole crop/grass yields.
Bottomland soils gave better DM yields for the than the Upland soils perhaps for being
more P-fertile. The overall low DM production was attributed to poor distribution of rains
at the study site and in-addition of fertilizers to the plots.
The average DM yields of sale C4 photosynthetic pathway cereals (Sudan grass and
finger millet) were 6.79 and 9.48 t/ha respectively in the long rains and 4.05 and 6.39 t/ha
respectively in the short rains. Herbage cuts at 90 DAS in the long rains showed
somewhat superior crude protein (17.5% CP) particularly of Sudan grass and Mealton 5
African clover compared to later harvests. Crude protein of grass herbage mixed with
clover legume herbage harvested at 105 and 120 DAS was higher than that in grass
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herbage alone, indicating that the clover added some premium value to the overall
herbage quality.
First, the agronomic finding that the shorter stemmed finger millet as a food crop showed
some promising associative compatibility with the African clover better than the African
clover intercropped with Sudan grass is important. Further more, the intercrop DM yields
plus some amount of good Crude Protein content level at the optimum 90-day maturity
has some agronomic significance. It could mean that the production of a potentially
fodder-bankable high quality zero-grazing (HQZ) resource | en |