COVER CROPS in South African Vineyards

CHAPTER 3 COVER-CROP SELECTION

TABLE 3.1. Continued.

Seeding density in kilogram per hectare

Common name

Scientific name

Paraggio bur or barrel medic Parabinga bur or barrel medic

Medicago truncatula ‘Paraggio’ Medicago truncatula ‘Parabinga’ Ornithopus sativus ‘Emena’ Trifolium fragiferum ‘Palestine’ Trifolium hirtum ‘Kondinin’ Trifolium michelianum var. balansae ‘Patrick’ Trifolium repens ‘Haifa’ Trifolium resupinatum ‘Maral’ Trifolium subterraneum ‘Clare’

25 25 25 12 16

Pink serradella Palestine clover

Rose clover

Balansae clover

4

White clover Persian clover

12 16 35

Clare subterranean clover

Mount Barker subterranean clover Trifolium subterraneum ‘Mount Barker’

35

Trikkala subterranean clover

Trifolium subterraneum ‘Trikkala’

35

Woogenellup subterranean clover Trifolium subterraneum ‘Woogenellup’

35

Assegaai clover

Trifolium vesiculosum ‘Zulu’

16

Faba bean

Vicia faba ‘Fiord’

120

Vicia (dasycarpa) villosa subsp. varia

Grazing vetch

50

Broadleaf purple or common vetch Vicia sativa ‘Lima’

50

The plants that performed best in the open-land trials were subsequently evaluated in vineyards.Vineyard trials were conducted over 10–12 years in the Coastal region, Breede River valley, and Olifants River valley.The sustainability of cover crops was compared to mechanical and herbicidal clean cultivation. In most cases, the cover crops were evaluated as monocultures sown year after year. However, it is recommended that grasses and legumes should be rotated, to prevent the build-up of soil-borne diseases that may target a specific cover crop.The rotation of cover crops is also important to prevent the development of herbicide resistance. By rotating grasses with broad-leaved cover crops, problem winter-growing broad-leaved weeds can be controlled with broadleaf-specific herbicides in the grasses, and winter-growing grass weeds with grass-specific herbicides in the broad-leaved cover crops.

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