COVER CROPS in South African Vineyards

COVER CROPS IN SOUTH AFRICAN VINEYARDS

LUCINDA HEYNS

that time. The effects, and importance, of rotations and mixed cover crops were researched only to some extent but are acknowledged throughout this book. Rotations and mixed cover crops became the subject of numerous other studies by different researchers, but one should never loose sight of the fact that all of that build on the information described in this book. Using monocultures are also sometimes necessary and beneficial. For instance, as described in this book, by planting a monoculture of a grass species, a problematic broadleaf species can be controlled with targeted chemicals that control broad leaf species only. Cover crops are also very important to control water run-off and erosion. In the book it is also clearly shown that using cover crops, and irrigating them for better growth, reduced the overall water usage of a vineyard. This was a very important finding as one of the serious concerns raised against cover crops was that it might increase the water usage of vineyards. In a water scarce country this would have been a serious drawback. Proving that cover crops, and using it as a mulch, decreased the overall water usage was thus a very important breakthrough. Research, especially long-term research, can sometimes be very monoto- nous.When you thus get lucky, and an unplanned event allows you to observe and measure something important it enlightens the day. One such an event was the heat wave experienced during one of the trials and the resultant measurements on the damage to bunches that differed markedly between treatments. See page 158.The researcher must, however, have the presence of mind to take advantage of these opportunities. Enjoy this book. It is the lifework of dedicated researchers.

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