COVER CROPS in South African Vineyards

CHAPTER 3 COVER-CROP SELECTION

3. Triticale and grazing vetch monocultures rotated every two years 4. Triticale and grazing vetch monocultures rotated every year 5. Grazing vetch.

Weeds

1,82

Dwarf fescue

1,98

2,11

Grazing vetch

3,96

Triticale + grazing vetch annual rotation

Triticale + grazing vetch two-yearly rotation

4,10

4,18

Rye + faba bean mix

Triticale

6,03

3,00

4,00 5,00 6,00 7,00

0,00 1,00 2,00

Dry matter in tonnes per hectare FIGURE 3.16. Long-term average dry-matter production of cover crops in the Breede River valley. Adapted from Fourie (2010).

In addition to its poor dry-matter production, perennial dwarf fescue was found to be a poor choice of cover crop, due to its negative effect on seasonal water use and grapevine production. Perennial dwarf fescue is also detrimental to the nitrogen status of young vines. Reference list Fourie JC. 2010. Soil management in the Breede River valley wine grape region, SouthAfrica. 1. Cover crop performance and weed control. South African Journal of Enology and Viticulture, 31(1), 14–21. Fourie JC, Louw PJE and Calitz FJ. 2006. Effect of seeding date on the performance of grasses and broadleaf species evaluated for cover crop management in the Breede River valley wine grape region of South Africa. South African Journal of Enology and Viticulture, 27(1), 8–14. Fourie JC, Ochse CH and Freitag K. 2018. The effect of irrigation by means of micro-sprinklers and drippers on the performance of triticale ( Triticale cv. Usgen 18) on a sandy clay loam soil in the Breede River valley. Wineland November, 62–64.

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