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Disease risks from yesterday's rain + meeting info.

Boy, it was some strong wind we experienced during a thunderstorm yesterday!  I saw a few trees fell down in the downtown Winchester.  That storm brought about 0.38 inches of water, the rain lasted about 80 min, then everything dried up very quickly.  This rain was a borderline case for downy mildew infection event.  This fungus (or oomycete, if you wan to be precise), can infect grape tissues in 90 min.  At the same time, it has been very dry for us, so, the overall risk may be low. 

Even though the critical time has passed for berry infection of downy and powdery mildew, you need to maintain your leaves reasonably healthy for your crop and also for next year (accumulation of carbohydrate to trunks).  Please keep scouting for powdery and downy by checking younger susceptible leaves on the top of canopies.

The weather forecast is showing a chance of rain tomorrow and Thursday.  I think we need little more rain for our vines...

FYI:
  • I will be out for a meeting until this Thursday.  If you need to contact me, email will be the best way.   I will try to update this page, if I have a good web access.  
  • Also, we will have a vineyard meeting at out Winchester AREC on August 4th from 11AM.  If you have time, please stop by.  You get to see vines full of powdery mildew!
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