COVER CROPS in South African Vineyards

CHAPTER 8 EFFECT OF COVER CROPS ON GRAPEVINE NUTRITION AND PERFORMANCE mix annual rotation

900

800

700

600

500

1994/95 1996/97 1998/99 2003/04

400

300

200

Nitrogen in milligram per litre

100

0

Triticale

Grazing vetch Rye|faba bean Triticale|vetch annual rotation mix

No cover crop

FIGURE 8.3. Nitrogen measured in the grape juice from vines in grass cover-crop treatments compared to a control in the Breede River valley. Full-surface chemical control was applied at the end of August. Adapted from Fourie (2011). tw -yearly rotati n fescue

900

800

700

600

500

1994/95 1996/97 1998/99 2003/04

400

300

200

Nitrogen in milligram per litre

100

0

Triticale

Grazing vetch Triticale|vetch two-yearly rotation

Perennial dwarf fescue

No cover crop

FIGURE 8.4. Nitrogen measured in the grape juice from vines in legume cover-crop treatments compared to a control in the Breede River valley. Full-surface chemical control was applied at the end of November, except in the dwarf fescue treatment. Adapted from Fourie (2011).

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