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Disease risks 7/21-22

Winchester area received a short rain event on the 21st.  It only lasted a short time, but due to that relative humidity stayed high for the whole night.  (i.e., it was a good condition for downy mildew to produce spores)  Then we received rains from about 4 PM yesterday.  It resulted in about 18 hours of wetness with an average temperature of 69F.  It was an infection risk event for downy mildew and Botrytis.   Our Chardonnay is getting close to veraison, so, we probably will think about Botrytis treatment on the next round of application.

(As I noted in the previous post, even though it was also events for black rot and Phomopsis, these disease should not cause major damages on your berries at this late in the season, unless you have chronic issue with Phomopsis.)
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