Constantia winegrowers lead the fight against the mealy bug

Monday, 25 October, 2004
Gustav Thiel
The farms of the Constantia Wine Route have pioneered an integrated and environmentally friendly way to fight mealy bug in vineyards. A working programme has been put into practice last month, a first in the world of wine.

Mealy bug infestation is responsible for the spread of the leaf roll virus in vineyards, which has potentially hazardous consequences for wine quality.

A technical group of the Constantia Wine Route was formed to find a 'green' way of keeping the mealy bug out of vineyards. The group consists of vineyard managers, viticultural consultants and chemical representatives.

Vinpro consultant Johan Pienaar says: 'The uniqueness of this approach is the fact that all the wine estates in the Constantia area is following the same strategy and working in unison to address the spread of mealy bug in vineyards.'

Wine producers around the world have until now been severely hamstrung in the fight against the bug by a lack of coordination. In several countries, most damagingly in Hungary, the bug has all but decimated certain areas under cultivation.

Members of the local technical group include Kallie Brocker from Groot Constantia, Lowell Jooste and Kobus Jordaan from Klein Constantia, Allen Cockroft from Glen Alphine, Johan de Swart from Steenberg, Peter Reynolds from Buitenverwachting, Steve Rouche from Eagle's Nest, Andre Rosseau from Constantia Uitsig, Gavin Dunn and Moller Nel from Terason and consultant Johan Wiese.

Adds Pienaar: 'The situation called for an integrated approach and I believe we have achieved that. But, perhaps more importantly, what we have devised a plan that will also prove to be environmentally friendly. It is fair to say that we are leading the way internationally in the fight against the bug.'

The plan involves the re-establishment of vineyards in a process that Groot Constantia winemaker Boela Gerber believes will take a human generation to complete. 'By re-establishing the vineyards and implementing the plan to make sure they stay clean, the Constantia ward is preparing the way for other wine producing areas in South Africa and the rest of the world to benefit,' enthuses Lowell Jooste, Klein Constantia's managing director.

The cornerstone of fight against the mealy bug and its damaging cargo is the development of a pheromone trap. Andries Tromp, manager of the scheme for the Integrated Production of Wine at Nietvoorbij outside Stellenbosch, says Constantia is an area where the mealy bug had to be eradicated in an environmentally friendly way, hence the genius of the pheromone trap. The trap enables vintners to easily monitor the occurrence of the mealy bug in the vineyards.

Carolus Davids will be one of the men who will monitor the mealy bug at Groot Constantia. He has been employed on the farm for 12 years. 'This trap is very simple because it uses a sticky pad to get the mealy bug trapped. I can already see that it is going to work,' says Davids.

In nature, says Pienaar, natural predators control the mealy bug. The pheromone traps enables vineyard managers to introduce the correct amount of predators into vineyards.

Each Constantia farm produced a detailed map of every block of grapes and are coloured green for being clean of the virus, orange for symptoms of leaf roll virus but clean from mealy bug, and red for symptoms of both. Labourers move from the green block through the orange block and end their work in a red block. All clothing should be sterilised thereafter.

Brocker says labourers have already been trained in the new methods and a new spirit of cooperartion on all levels is present in the vineyards of Constantia.
Constantia Uitsig's Rosseau believes, while the revolutionary plan to keep the mealy bug off vineyards will enhance labour practices, it will also be 'very green friendly because it is a lot more organic and will for instance not kill ladybugs in vineyards.'

'The mealy bug has become a big issue around the world, but I think we are now on the way to making sure that it does not affect the process of making top quality wines in the future,' concludes Rosseau.

By Gustav Thiel for the Constantia Wine Route

For further enquiries about the mealy bug and its eradication contact Lowell Jooste at 082 441 3721

For any media enquiries contact Gustav Thiel at 083 708 3052