COVER CROPS in South African Vineyards

9

FIGURE 9 .1. Damage to vine leaves by white dune snails. (Photo: ARC Infruitec-Nietvoorbij).

PESTS

Cover crops can play an important role in reducing the prevalence of grapevine pests. For example, cover crops can provide a refuge for beneficial insects such as predatory mites, particularly during winter. Predatory mites contribute to the control of pests such as red spider mite. Cover crops can also help to limit pests by suppressing weeds. For example, banded fruit-weevil larvae feed and develop on the roots of various broad-leaved weeds, such as narrow-leaf ribwort, during winter.The adult weevils then move up into the grapevines when the weeds start dying in spring and summer. By cultivating a cereal cover crop which is not a host plant for these pests, banded fruit weevil numbers can be reduced.

This chapter summarises research on

the interactions of cover crops with pests. As these studies were mostly conducted at a single site, the information is organised by pest, not by region.

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