22 April 2005
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Content:
O-GEN Linked to Ohio Grape Web
Grape Disease Control
Pest Alert…Grape Flea Beetle
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As you may notice, we keep modifying and improving this electronic newsletter as we go. One of the problems with previous issues is that some recipients were not able to receive attachments due to file size restriction from their Internet providers. To fix, this problem, we made the newsletter available on our current website http://www.oardc.ohio-state.edu/grapeweb/ (which is also undertaking major reconstruction). Hope this would solve the problem especially with large-sized files. As always, please send me your feedback, comments, and suggestions.
This is not a mistake! You have already received a similar article in the previous issue. The attached article, GRAPE DISEASE CONTROL, 2005, by Dr. Wayne Wilcox , Cornell University, Geneva is a supplement and contains a tremendous amount of good information on grape disease control in the Eastern U.S. Dr. Wilcox puts out this article each year and he has graciously agreed to share it with us. I strongly encourage all Ohio grape growers to read the article.
Its spring and with bud swell comes the first pest of the season, the grape flea beetle. This metallic steel blue or greenish blue beetle is about 3/16 of an inch long and can do serious damage to the flower buds, while they are still in the swollen stage. The threshold used to determine if there is need for intervention with a spray is at 5 % bud damage, when the buds are just beginning to swell. They chew holes in the ends and sides of the buds damaging the developing flower within. Once the buds begin to open the threat to the developing flower within diminishes. Female beetles lay eggs mainly under loose bark on the grape vine. Larvae hatch and begin feeding on developing grape leaves. Damage by the larvae and adults feeding on the young leaves is usually spotty and not severe. Adults can be seen on canes and buds on warm sunny days in April and May. Flea beetle damage is often concentrated in vineyard borders and near wooded or brushy areas. Spot treatment may be all that is needed to control this pest.
Control recommendations see: Midwest Commercial Small Fruit and Grape Spray Guide 2005. http://www.ag.ohio-state.edu/~sfgnet/. Pesticides recommended are Sevin and Danitol.