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Rains in the forecast, and a vineyard meeting at Pollak Vineyards

There is a vineyard meeting tomorrow at Pollak Vineyards from 11 am. I won't be there, but here is my handout for tomorrow, which talks about risks of diseases at this point and a disease update at Winchester. Tony will be there to discuss about viticulture topics.

There are chances of rain in next few days in the forecast. However, so far, we haven't had a night which favors downy mildew sporulation for a while. In addition, your berries should be developing resistance to downy mildew and powdery mildew at this point (4-5 weeks after bloom).

For black rot, it may take little longer (up to 8 weeks after bloom, depends on variety), thus, please scout your vineyards for black rot. Black rot fungus takes about 2 weeks from infection to sporulation. Thus, you do not see it right now, your risk is low because there is not enough time to have an outbreak. If you have some degree of infections on berries and leaves at this point, and if you are concerned, Rally (myclobutanyl) is a good product that you can apply after the rain.

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