COVER CROPS in South African Vineyards

COVER CROPS IN SOUTH AFRICAN VINEYARDS

which cover crops are planted, and how they are managed. Pests in Chapter 9 (p166) describes trials that have examined the interactions between cover crops and snails, ants, mealy bugs, and nematodes. It is worth mentioning that the studies discussed in Pests in Chapter 9 (p166) did not find any evidence of cover crops encouraging pests. The importance of the physical condition of the soil Grapevine roots find it easier to penetrate loose than compacted soil. The correct physical soil characteristics will promote the development of a large, healthy root system, whereas soil compaction will limit root growth (Figure 1.4). This is why the soil is loosened to a depth of 800–1 000 millimetres when preparing to plant vines.

FIGURE 1.4. Restricted root growth in a non-bearing vineyard due to recompaction caused by mechanical soil cultivation after soil preparation. (Photo: ARC Infruitec-Nietvoorbij).

The problem is that the prepared soil is readily recompacted by the actions involved in establishing the vineyard.Tractor and implement traffic commonly cause recompaction when tractors are allowed on prepared soils, so this should be avoided at all costs (Figure 1.5).

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