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Rate of sulfur treatment

Tony sent out March-April issue of Viticulture Notes yesterday. Along with the newsletter, he sent my fungicide spray guideline for 2010. If you haven't received it, please let me know so that I can put you on Tony's email list.

On that guideline, Ms. Lucie Morton found that I stated the rate of wettable sulfur was 5-10 lb/A and notified me that it should be lower. Although the label allows you to go that high, I agree with Lucie. It really depends on the formulation, so, I cannot give you the exact number for each, but we used Microthiol Disperse at 3-4 lb/A last year and it provided a good control.

As I stated at the beginning of the guideline, it is merely a guideline. You need to adjust for your particular situations. Also, please follow the label for the rate, because I cannot cover all possible combinations of chemicals, especially the one with many generics, such as sulfur.

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