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It was a nice and dry weekend

I hope all of you had a nice 4th of July weekend. I'm glad that we did not see the forecasted thunderstorm events.

Most of vines should be approaching the end of the critical period for powdery mildew, downy mildew, and black rot infection on berries. Berries of V. vinifera varieties become resistant to infection after 4-5 weeks after bloom. (V. labrusca vines become resistant after 2-3 weeks, hybrid varies.) These pathogens still can infect, but the success rate declines rapidly after this period. In Winchester, >50% bloom was observed on Chardonnay on 6/6/09 and on Cabernet sauvignon on 6/9/09; thus we have about a week to 10 days to go.

After this critical period, weather condition in VA typically becomes unfavorable for downy mildew and black rot (hot and dry), and powdery mildew control becomes a key issue. Please scout your vineyards for diseases and adjust your spray schedule accordingly. Also, this is about the time Japanese beetle becomes an issue. I've heard that wet spring tends to support their population, so, keep your eyes on them too.
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