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Rain after rain....

We had a series of thunder storms on Wednesday and last night. The condition of air were dry to begin with, so, the relative humidity did not stay high after the rains (stayed in 70% range). Thus, these rains probably did not account for disease event at Winchester; however, your vineyard might had more rain or longer rain. Please check your local weather.

Also, we are still having 7 consecutive nights with conditions for downy mildew sporulation. Even with a short rain (>90 min), it can cause an infection, thus, if your berries are still in a critical time (4-5 weeks after bloom), and you see leaves with downy mildew in your vineyards, then you may need to react to these series of infection event with Phosphorus acid or Ridomil products. However, if your berries passed the critical time, the risk of infection is very low.

Once again, the fungus you may need to concern at this point is Botrytis. Make sure to protect your bunches with Botrytis materials (please read previous posts (2-3 post ago) for details).

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