Grass, legumes and maize a basis for massive expansion in animal production in Rhodesia

No Abstrac

Pasture research in Zimbabwe : 1964-84

In IDL-684

Recherche sur les pâturages au Zimbabwe : 1964-1984

Réunion: Recherche sur l'amélioration des pâturages en Afrique orientale et australe, 17-21 sept. 1984, Harare, ZWDans IDL-792

Screening of legumes for veld reinforcement.

In order to test their suitability for veld reinforcement, Desmodium intortum, D. sandwicense, D. uncinatum, Glycine wightii, Listia heterophylla, Lotononis bainesii, Macroptilium atropurpureum, Stylosanthes fruticosa, S. humilis and three strains of S. guianensis were seeded in December 1970 in disced veld at Marandellas (sand) and near Mazoe (clay). Starting in December 1971 the legumes were grazed in common at two stocking intensities during the wet season only, the dry season only or year-round, using a simulated rotational grazing system. Legume seedling mortality was high on the sand and only M. atropurpureum and the five Stylosanthes lines had plant densities in the second season greater than 1 plant/m 2. On the clay establishment was better and all legumes except L. heterophylla had densities greater than 1 plant/m 2. Oxley fine-stem stylo was the only legume to persist and spread on the sand but on the clay a much wider range of legumes persisted, although all were adversely affected by a hot fire in July 1976. D. uncinatum, L. heterophylla and L. bainesii were the most persistent legumes on the clay and spread widely. Grazing treatment did not greatly affect the persistence or spread of the legumes. However, at both sites the frequency of the undesirable grass Sporobolus pyramidalis increased in the plots grazed during the wet season. On the clay this was associated with a reduction in the frequency of Hyparrhenia spp. The possible shortcomings and the applicability of this type of trial are discussed.Keywords: botany; clay; desmodium intortum; desmodium sandwicense; desmodium uncinatum; establishment; fire; glycine wightii; grass; grasses; grazing; legumes; listia heterophylla; lotononis bainesii; macroptilium atropurpureum; marandellas; mazoe; mortality; persistence; plant density; rotational grazing; sand; season; sporobolus pyramidalis; stylosanthes fruticosa; stylosanthes guianensis; stylosanthes humilis; veld reinforcement; zimbabw

A comparison of irrigated grass-clover and nitrogen-fertilized grass pastures for beef production.

An area of irrigated sandveld was planted in December 1971 with Panicum coloratum and fenced into eight paddocks, four of which were later seeded with Trifolium semipilosum. The P. coloratum grew poorly and the pastures were later interplanted with Cynodon aethiopicus, which also did not thrive, and with Pennisetum clandestinum, which did. The grass-clover pastures were initially clover-dominant but had attained a reasonable grass: clover balance by the end of the trial.The pure grass pastures were fertilized with 450 kg N/ha in 1973/74 and 500 kg N/ha in 1974/75 and 1975/76.Grazing started in February 1973 with a policy aimed at producing fatstock for the high-priced Christmas period. Three groups of steers have been slaughtered off the trial. The carrying capacity and productivity of the two pasture types have been very similar. As the N applied to the pure grass pasture currently costs R$ 166/ha/annum, the reduction in costs from the use of clover has been considerable. Problems have, however, been experienced with scouring and bloat on the grass-clover pastures.Keywords: beef production; carrying capacity; clover; cynodon aethiopicus; grass; grasses; panicum coloratum; pastures; pennisetum clandestinum; productivity; sandveld; trifolium semipilosum; zimbabw

Methods of pasture establishment

In IDL-684

Effects of legume reinforcement of veld on the performance of beef steers.

To measure the effect of legume reinforcement of veld on animal production, a 24 ha block of reverted granite sandveld dominated by Hyparrhenia filipendula was fenced into 8 equal-sized paddocks, 4 of which were seeded with legumes. Two paddocks were seeded in December 1971 with a mixture of Stylosanthes humilis, S. guianensis var. guianensis cv. Schofield and an erect-growing strain, S. guanensis var. intermedia cv. Oxley (fine-stem stylo) and, S. fruiticosa and two in January 1973 with a mixture of fine-stem stylo and Macroptillium atropurpureum cv. Siratro. Full-time grazing of the trial started in June 1973 with a cattle policy aimed at growing out weaner steers and then removing them after a year for pen finishing. Until January 1975 both sets of paddocks were stocked at the same rate; after that more cattle were carried on the legume-reinforced paddocks. The mean annual gain per head was 118 kg on the control of 161 kg on the reinforced veld. Mean annual bodymass gains per hectare were 116 and 177 kg respectively. The rates of gain of the two groups of steers were similar during the main growing season but cattle on the legume-reinforced veld performed better during the late growing season and the dry season. The density of fine-stem stylo increased during the course of the trial while that of the other strains of Stylosanthes and of Siratro decreased.Keywords: animal production; beef steers; cattle; granite; grasslands research station; grazing; hyparrhenia filipendula; legumes; macroptilium atropurpureum; marandellas; performance; production; reinforcement; rhodesia; sandveld; stylosanthes fruticosa; stylosanthes guianensis; stylosanthes humilis; veld; zimbabw

Méthodes d'implantation des pâturages

Réunion: Recherche sur l'amélioration des pâturages en Afrique orientale et australe, 17-21 sept. 1984, Harare, ZWDans IDL-792

Possible role of forage legumes in communal area farming systems in Zimbabwe

Meeting: Workshop on Forage Legumes in Farming Systems of Sub-Saharan Africa, 16-19 Sept. 1985, Addis Ababa, E