COVER CROPS in South African Vineyards

COVER CROPS IN SOUTH AFRICAN VINEYARDS

The failure of legumes to re-establish in the Coastal region trials was attributed to the lack of scarification of their hard-coated seeds in the sandy loam soils of this region. Reference list Fourie JC, Louw PJE and Agenbag GA. 2006. Cover crop management in a Chardonnay/99 Richter vineyard in the Coastal wine grape region, South Africa. 1. Effect of two management practices on selected grass and broadleaf species. South African Journal of Enology and Viticulture , 27(2), 167–177. Lower Orange River region Trials in the Lower Orange River region were conducted over a period of four years to assess the effect of different management practices on the ability of cover crops to re-establish.The study was carried out on the farm Boomplaas in Keimoes, near Upington in the Northern Cape. Seven cover crops were evaluated: rye, Overberg oats, black oats, grazing vetch, Woogenellup subterranean clover, Paraggio bur medic, and pink serradella. Dry-matter production of plants that were resown annually was compared to that of plants that were allowed to seed themselves. Where plants were resown annually, full-surface chemical weed control

was applied from the first week of August, before grapevine bud-break.Where plants were allowed to complete their life cycles and produce seed, full-surface chemical control was only applied from véraison. The results of the trial are summarised in Figure 4.2. Although the grasses did, in most cases, re-establish, the dry-matter production of the self-seeded grasses never reached even a third of the dry-matter production of the same grasses when sown annually.

THE DRY-MATTER PRODUCTION OF SELF-SEEDED GRASSES NEVER REACHED EVEN A THIRD OF THE

DRY-MATTER PRODUCTION OF THE SAME

GRASSES WHEN SOWN ANNUALLY.

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