Simonsberg between Stellenbosch, Paarl and Franschhoek looked like "an erupting volcano" late yesterday. The fire, burning since Tuesday midday, had spread across 90km from Idas Valley, Simondium, to Paarl threatening farms on the foothills of the mountain, Craig van Reenen of Stellenbosch Fire Department said.Giles Webb, owner of Thelema at the top of Helshoogte Pass, said: "At the end of the December I thought that this year would be one our best vintages. But that idea has gone up in smoke."Webb said the fire had affected about 15 hectares of his farm to varying degrees, including blocks of chardonnay vineyards."We can't determine yet how many vines we've lost. We'll only know next spring. But even if some survive you don't want gaps in your vineyards. We'll have to replant, which costs R200 000 a hectare."This is not a good situation. This fire will have a big economic cost. All the vineyards against he mountain were affected."About 200 firefighters from various organisations were working to put out the fire, with farmers and their employees working together to protect their land, crops and buildings.Van Reenen predicted the battle would continue for at least the next three days.He said there was no confirmation of what had caused the fire. "At the moment we're focusing on fighting the fire."Fransie Roux of Tokara wine farm said yesterday: "Our people worked till 5am fighting the fire."Mark Lester, also of Tokara, said: "We've never had such consistent wind and heat at this time of the year before."Volunteer Wildlife Services warned yesterday on its website that the consistent hot, dry and windy conditions were conducive to the ignition and spread of wildfires.André Morgenthal of Wines of South Africa said a large section of Delheim's forest had burnt. The forest, he said, was owner 'Spatz' Sperling's pride and joy. Fortunately, Delheim didn't lose vineyards, but the nearby farm Zorgvliet did."It's very bad. But we're not sure what the impact will be on each brand," he said.Not only is the burning of vineyards a problem, but the smoke may taint the flavour of the wine.Rustenberg Wines, Uitkyk Wine Estate and Kanonkop Wine Estate were all battling fires late yesterday.Last night, Van Reenen couldn't confirm how many farms in total were affected...