Virginia Grape Disease Updates

  In preparation for hurricane Ida, here is some information that you may find useful (This is a repeat of the previous post, but I received some emails asking for them.) 1)  List of short PHI fungicides for late-season diseases (will open a pdf file) 2)  Updated presentation from the last virtual field day (will open a pdf file). Recent downy mildew risks Many of us have been experiencing more rains lately than the past several months, here are a number of days with downy mildew risk events in the past two weeks based on the NEWA’s DMCast. Many of these rains have been sporadic in terms of area and time it covered, so, use these numbers as a guide. Bristol: 14 days (latest was on 8/30) Floyd: 9 days (latest was on 8/29) Charles City: 14 days (latest was on 8/30) Tyro: 7 days (latest was on 8/30) Red Hill: 5 days (latest was on 8/29) Washington: 8 days (latest was on 8/29) Winchester: 9 days(latest was on 8/29) It is probably a good idea to protect your vines against down...

Recent rains and more rains in the forecast made me think of downy mildew. Let's take a look at what the NEWA DMCast model says about downy mildew risks from the past two weeks. Westfield, NC (South of Stuart, VA) There were six DM risk events, including one that happened today.  (Note: we have a new weather station in Bristol. You can check the weather data, but the DMCast model is not working yet. I notified the NEWA about the lack of DMCast outputs.) Floyd, VA There were four days with downy mildew risk event(s) since the beginning of the month. Red Hill There were four days with downy mildew risk event(s) since the beginning of the month. Washington, VA There were nine days with downy mildew risk event(s) since the beginning of the month. Winchester, VA There were five days with downy mildew risk event(s) since the beginning of the month. It looks like there were more downy mildew risk events as we move northwards. Also, recent warm and humid nights can promote the downy mildew...