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Handouts from the 2012 VVA meeting

First of all, a (belated) Happy New Year!  I meant to upload some posts in January, but things were bit busy.

Second, thank you for those of you who attended the 2012 VVA meeting.  It was very nice to talk to many of you at the meeting, and I am looking forward to meet you at either IPM workshops (Place and time, TBD, but we are planning to have it at multiple locations at the end of March, please check this blog and also email from Tremain), or in-season vineyard meetings.

Third, I have been asked from several of you to upload a color copy of presentations from the meeting, so here you go.  This link downloads a pdf file from the beginner's workshop, and this link is for a pdf file of the talk about fungicide trials and discussions for 2012 season. (By the way, what I meant by "bee" in the presentation was "yellow jacket" as many of you have pointed out!  ;) )

Next, many of you have asked me about pruning wound protection.  As Tony described in the precious Grape Press, you can apply a product called Topsin-M to pruning wounds because VA has a special label. (i.e., it may not apply to your state, please check with your local extension agents!)  Here's a link to my older post about the use of the product, which also contains a link to the special label.  Please make sure to read the label.  It has a 2-day REI. thus you cannot go back to the vineyard for 2 days. This product will give you a protection against Bot canker which can enter through pruning wound.  Bot canker (caused by several Botryospaheria species) may or may not develop symptoms within a year or two, but there are evidence of long-term effect of this disease complex.  If you are thinking about using it, please consider spray or paint only a part of your vineyard (= leave some part of vineyard untouched), so that you can obtain comparative data.  If you wish, we can even set up a demonstration plot.  Please contact me if you wish to talk about it.

Of course, the fungicide application is not the only measure against Bot canker, and I recommend you to think about alternatives.  The double pruning that Tony described in Grape Press has been shown to very effectively protect your vines, and also I recommend not to prune if you see rains in the forecast.  As with many other fungal diseases, Bot canker pathogens require water to be disseminated and to initiate infection.  Also, if you will give a time for pruning wounds to heal, there should be lower chance of infection.  Thus, it is better to prune when weather is warmer because the wounds tend to heal faster.  In normal winter weather conditions, we probably do not have a high risk around this time of the year because the temperature is very low, but warm temperature we are experiencing and rains we have make me worry about Bot cankers.

Finally, as I mentioned at the meeting, our leafroll survey is about to be done; however, we are still accepting samples.  We found very high number of virus-infected vines from our survey, thus, we would like to know more about them.  If you would like to test your vines for leafroll viruses, please let us know.  Thanks to the VA Wine Board, there will be no fees for testing.


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