Virginia Grape Disease Updates

As with many other places in the VA, we were suffering from frost damages.  We experienced several near freezing events this year, and most notably, a few hours of 25F on Thursday morning. Our younger Chardonnay planting (4th leaf) had a bud break around 4/1, and being suffered more from it.  I estimated about 80-90% of emerged shoots are now gone. Our older Chardonnay (8th leaf) is about a week behind, and my visual estimate as of yesterday was about 25% loss.  Some buds/shoots look like they are surviving, but I am not sure how it will go after tomorrow morning... There is a very nice blog post about spring frost from Dr. Michela Centinari at PSU.  If you are interested in, please follow this link. The other items I noticed in our vineyards is damage from climbing cut worm. For us, it always starts from the Eastern side of our vineyard which is facing a small patch of wood.  If it is a warm weather, I would spray for it, but I think I will wait ...

Our 6 years old  Chardonnay had 100% bud break today (4/22/2015)!  Looks our our season has officially started. There has been a few email inquiries came to my inbox about climbing cutworm.  We have applied Intrepid to "hot spot" which is a few panels facing wooded area for us.   Please refer to Doug's posting and UC IPM for more information.

The two hot days we had pushed things quickly.  Our Chardonnay buds are swelling and some are even broke.  Our Merlot is bit behind, but not by much.  Cab sauvignon seems to be still tight.  Looks like the season will start very soon!  Since we saw a bit of damages, I applied climbing cutworm treatment to the area of vineyard where we historically have issues.

Wow, we had another above 90F day here in Winchester. As of noon today, Chardonnay was 100% bud break with about 50% of them had fully expanded lower leaves. Cabernet sauvignon was about 30-50% bud break (variable with vines), some with fully expanded lower leaves. We are still expecting rain from tomorrow night to Wednesday. (60% chance of precipitation) This is an example of cutworm damaged leaf. Surprised to see it coming up with half a leaf gone, though.

We have seen some damage due to climbing cutworms on Chardonnay. Since I'm not an entomologist, I'll refer to Dr. Pfeiffer's page for the description of the insect. Virginia Tech's grape diseases and insects in vineyards has spray recommendations for cutworms. Some chemicals listed in the guideline can be harmful to beneficial insects such as bees which are very active right now with apple blossoms. Please refer to the label before you apply it. When you are in doubt, please consult local extension agents.