Low-input weed management and conservation tillage in semi-arid Zimbabwe

Four weeding systems were evaluated for three seasons on sandy soils in a semi-arid area of Zimbabwe. Inter-row weeding with a plough with body (mouldboard breast) attached, produced a ridge and furrow landform. This confers the advantage of increased water retention associated with ridging without the additional investment in labour and equipment needed when ridges are made pre-planting with a ridging plough. Mid-season ridging by plough with body attached achieved more efficient weed control than the common farmer practices of using a cultivator or plough without the body. In terms of crop water use efficiency and grain yield, weeding with the plough and body performed at least as well as any existing farmer practices. Productivity, in terms of grain yield per hour worked, was considerably higher following weeding with the plough and body compared with alternative systems.