COVER CROPS in South African Vineyards

CHAPTER 3 COVER-CROP SELECTION

3. Paraggio bur medic 4. Black oats 5. Grazing vetch 6. Parabinga bur medic 7. Overberg oats 8. Triticale. Reference list

Fourie JC. 2007. The evaluation and management of different grasses and legumes as potential cover crops in the vineyards of South Africa. Doctoral dissertation. Stellenbosch: University of Stellenbosch. Fourie JC, Louw PJE and Agenbag G. 2001. Effect of seeding date on the performance of grasses and broadleaf species evaluated for cover crop management in two wine grape regions of SouthAfrica. South African Journal of Plant and Soil 18(3), 118–127. Fourie JC, Louw PJE andAgenbag GA. 2005. Cover crop management in a Sauvignon blanc/Ramsey vineyard in the semi-arid Olifants River valley, South Africa. 1. Effect of management practices on selected grass and broadleaf spe- cies. South African Journal of Enology and Viticulture 26(2), 131–139. Winter-growing weeds that can be used as cover crops Cover crops in vineyards are grown during winter, and controlled chemically before bud-break, to prevent them from competing with the grapevines. Winter-growing weeds that germinate in autumn and complete their life cycle in spring can therefore serve as cover crops in situations where the selected grasses and legumes cannot be established. Four annual grasses with cover-crop potential (oat-seed grass, ripgut brome, common wild oats, and wild barley) are described below. These grasses were successfully managed as cover crops on a farm in the Breede River valley. However, readers should keep in mind that some of these grasses are serious weeds in other crops, and may therefore not be suitable for all sites. All four these annual grasses should produce seed by the end of September or by early October. Full-surface chemical control in early October is therefore advocated, as it will allow the grasses to re-establish in the following

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