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Recent downy mildew risk events

 It seems that several rain events have happened over the course of the past two weeks or so. Here is a summary of recent downy mildew risk events, based on the NEWA stations and DMCast.

Bristol, VA

Fifteen days with potential DM infection event(s) since Sept 1. The latest event happened last Sunday.

Floyd, VA



Eleven days with potential DM infection event(s) since Sept 1. The last event happened last Friday.

Charles City, VA


Twelve days with potential DM infection event(s) since Sept 1. The latest event happened yesterday.

Central VA

Since there was a wide variation among stations, I am listing several around Central VA.

Tyro, VA


Nine days with potential DM infection event(s) since Sept 1. The latest event happened yesterday.

Red Hill and Crozet, VA

Only one day with potential DM infection event(s) since Sept 1.

Olympic Lake


Thirteen days with potential DM infection event(s) since Sept 1. The latest event happened last Sunday.

Washington, VA


Eight days with potential DM infection event(s) since Sept 1. The latest event happened last Sunday.


Winchester, VA


Seven days with potential DM infection event(s) since Sept 1. The latest event happened last Friday.

Some rain events are sporadic and the amount of rain or length of leaf wetness can vary even within a few miles. Thus, please make sure to check your local weather. 

In general, it is probably a good idea to protect your vines against downy mildew this time of the season, and if you think your previous application was washed off from the rains, add a phos acid to your tank mix for your next spray.

List of short PHI fungicides for late-season diseases (will open a pdf file)


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