COVER CROPS in South African Vineyards

CHAPTER 3 COVER-CROP SELECTION

TABLE 3.3. The seeding dates and performance for grasses and legumes evaluated in vineyards in the Coastal region. Cover crops are ranked by dry-matter production. Adapted from Fourie et al (2001).

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

Common name

Seeding date

Grasses Black oats*

1–9 April 1–9 April 1–9 April 1–9 April 1–9 April

5.52 4.95 4.59 3.37 3.03 1.82 6.78 4.38 4.23 4.02 3.85 3.64 3.45 3.18 3.07 2.98 2.65 2.60 2.16 1.85 1.76 1.03 0.68 0.46 0.43 0.20

0.40 0.70 0.63 0.76 0.75 1.00 1.57 0.53 1.03 1.35 0.45 2.04 1.94 0.85 2.44 0.53 0.38 0.91 2.32 1.81 1.44 2.29 1.14 1.49 2.46 2.58

Overberg oats*

Rye*

Triticale

Barley

Perennial phalaris or bulbous canary-grass 19–22 March

Legumes Faba bean*

1–9 April 1–9 April 1–9 April

Parabinga bur or barrel medic*

Kelson snail medic*

Grazing vetch*

19–22 March

Paraggio bur or barrel medic*

1–9 April

Pink serradella

19–22 March 19–22 March

Broadleaf purple or common vetch Woogenellup subterranean clover*

1–9 April

Harbinger medic

19–22 March

Trikkala subterranean clover Clare subterranean clover

2–5 May 2–5 May 2–5 May

Mount Barker subterranean clover

Rose clover

19–22 March 19–22 March

Assegaai clover Persian clover

1–9 April 1–9 April 2–5 May 2–5 May 1–9 April

Campbell annual lotus

White clover

Balansae clover Palestine clover

Gabriel perennial lotus

19–22 March

* 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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