COVER CROPS in South African Vineyards

COVER CROPS IN SOUTH AFRICAN VINEYARDS

TABLE 3.2. The seeding dates and performance of grasses and legumes evaluated in open-land trials in the Breede River valley. Cover crops are ranked by dry-matter production. Adapted from Fourie et al (2006).

Dry-matter production in tonnes per hectare Cover crop 1 Weeds 2

Common name

Seeding date

Grasses Triticale*

13–18 April 13–18 April 13–18 April 13–18 April

8.79 7.07 6.89 6.44 3.81 2.25 7.10 5.67 4.56 3.78 3.73 3.30 1.65 1.55 1.46 1.36 0.99 0.98 0.97 0.87 0.77 0.63 0.48 0.19 0.06 0.05

0.20 0.27 0.23 0.17 1.26 1.96 0.39 0.42 0.70 1.20 1.70 1.17 2.55 3.03 3.12 2.30 2.31 2.45 2.87 3.49 3.01 2.63 2.71 3.85 4.07 3.05

Overberg oats

Black oats

Rye*

Barley

1–4 May 1–4 May

Perennial phalaris or bulbous canary-grass

Legumes Faba bean*

8–11 April

Paraggio bur or barrel medic

24–26 March 24–26 March 24–26 March 24–26 March 24–26 March 24–26 March 24–26 March 24–26 March 24–26 March 24–26 March 24–26 March 24–26 March 24–26 March 24–26 March 24–26 March 8–11 April 8–11 April 1–4 May

Grazing vetch*

Parabinga bur or barrel medic Broadleaf purple or common vetch

Kelson snail medic

Persian clover

Clare subterranean clover

Mount Barker subterranean clover

Pink serradella

Woogenellup subterranean clover

Gabriel perennial lotus

Harbinger medic

Trikkala subterranean clover

Assegaai clover

Rose clover

Palestine clover Balansae clover

White clover

Campbell annual lotus

8–11 April

* plants that were included in long-term vineyard trials. 1 cover-crop dry-matter production below 2.5 tonnes per hectare is considered too low for weed suppression. 2 weed dry-matter production above 1.0 tonne per hectare indicates insufficient suppression.

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