This deep understanding of the culture of wine farming, as well as the realization that the usage of potent chemicals is unsustainable, has led the farm manager of Vergelegen, Rudolf Kriel to begin the journey of moving away from the use of chemical pest management, to integrated pest management.
RealIPM had the opportunity to meet with Rudolf in the vineyards of Vergelegen, and he kindly shared with us his strategy and plans for the farm. Rudolf explained that Vergelegen is a certified member of International Fairtrade and Integrated Production of Wine (IPW). In order to adhere to environmentally friendly certifications and to continue moving towards long term sustainable farming practices, Rudolf has undertaken the following changes:
Reduction in chemical usage
Over the past couple of years, Rudolf and his team have begun reducing the usage of heavy chemicals and herbicides. The main aim of this process is to reduce the dependance on chemicals for pest management, and to also reduce residue from chemicals on the grapes. Cereal crops are grown between rows which helps to suppress weed growth, build organic matter, and to increase diversity.
Bringing back avian predators
Rudolf described how during one particular season; he was inundated with rodents. The furry pests were destroying young shoots and eating up seedling before they even had a chance to take root. Rather than using exterminators or poison, Rudolf added several wooden poles and structures to the vineyards. This allowed various birds of prey, such as owls and kites to return to the vineyards and watch from their posts for their next meal. It worked so well, Rudolf now tells us that there are so many owls at night, it’s like an opera of bird song.
Utilisation of beneficial insects
(Left) Predated mealybug, (Right) Beneficial insects being released
Vine mealybug is a common pest in vineyards across the Cape, and the world. These white scaley pests suck the sap from the vines, reducing plant vigor, while they excrete sticky honeydew and wax, which reduces plant and fruit quality, especially when black sooty mold grows on the honeydew. They are also carriers for leaf roll virus, which is deadly to vines and cannot be treated. Mealybug has shown resistance to many of the common chemicals used, and often spraying chemicals which have a long persistence (such as organophosphates) can result in an even worse outbreak. At Vergelegen, they have opted to rather deal with mealybug by using beneficial insects. These insects are predators of mealybug and depending on the lifecycle stage of the mealybug can be highly effective in managing these pests. The diagram below showcases the various beneficial insects that realIPM uses to manage mealybug. At Vergelegen, Real AnaFIX and Real PermiFix, two predatory wasps who lay their eggs in the mealybug, as well as Real CryptoFIX, who loves to eat mealybug, are the most utilised beneficial insects. Our realIPM technical expert, Alexandra McFarlane also works alongside Rudolf and performs regular scouting checks, every 2-3 weeks. This ensures that if there are any hot spots of insect activity, beneficial insects can be released at the exact site to ensure optimal efficacy.