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Early season disease management

Looks like we are expecting three days with high chance of rain from Monday.  I sprayed our vines with mancozeb (3 lb/A) and sulfur (3 lb/A) yesterday.

At this point of the season, my target fungal disease is Phomopsis since this pathogen can be active in relatively cool rain event, and we have relatively old vines (~23 years old) right next to our newer Chardonnay.  Mancozeb comes in handy because it also has efficacy against black rot and downy mildew.  These diseases typically develop little later in the season, but it is much easier to protect your vines from them than try to counter-act to the developing diseases.  I also added sulfur to add an insurance against powdery mildew. 
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Comments

  1. UnknownMay 8, 2013 at 9:12 PM

    If we didn't spray before the rain would it do any good to spray after or should we wait to spray until before the next rain?

    ReplyDelete
  2. Mizuho NitaMay 9, 2013 at 4:01 PM

    Hi Gray,
    Please see today's posting. A few people had the same question.

    ReplyDelete

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