Sulphur burn - UPDATE 7/1/2014

Above: Some sulphur fungicide burn from a Shiraz vineyard sprayed during the hot weather. Note the vines are still growing very rapidly. (c) James Hook
When applying powdery protection avoid spraying wettable sulfur at high temperatures (35oC) when the humidity is above 70% within 24 hours of spraying.
Above: Sulphur burn on Frontignac. (c) James Hook
Growers can opt to use the fungicide Legend (Active Ingredient: quinoxyfen, Fungicide Group: Group 13) in hot weather to avoid sulphur burning. This allows them to keep up the powdery mildew protection on their vineyard. Legend has a 45 day Withholding Period (Vintage 2014). Legend costs $24.40 per hectare at its maximum rate (20ml/100lts) assuming a 1000lt dilute spray volume (DSV).