COVER CROPS in South African Vineyards

COVER CROPS IN SOUTH AFRICAN VINEYARDS

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Phosphate in milligram per kilogram soil

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FIGURE 7 .9. Soil phosphate measured in the 0–150-millimetre soil layer in cover-crop treatments over four years at Blaauwklippen in the Coastal region. Adapted from Fourie et al (2015).

matter and macro-nutrient content of a medium-textured soil. South African Journal of Enology and Viticulture , 28(1), 61–68. Fourie JC, Kruger DHM and Malan AP. 2015. Effect of management practices applied to cover crops with bio-fumigation properties on cover crop performance and weed control in a vineyard. South African Journal of Enology and Viticulture , 36(1), 146–153. Olifants River valley A trial in the Olifants River valley was conducted at the ARC Infruitec- Nietvoorbij research farm near Lutzville in the West Coast District of the Western Cape. Seven cover crops, namely Henog rye, Overberg oats, Saia black oats, Paraggio bur medic, Parabinga bur medic, pink serradella, and grazing vetch, were compared to a control without a cover crop. Organic carbon The trial site had sandy soils with less than 1% clay. Soil organic carbon in 1993, at the start of the trial, averaged 0.12%, and was not significantly different in the different treatment plots.

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