Question: What is causing this problem with the leaves on my grape vine?

Answer: My first guess would be Esca. Its a disease/disorder that no real causal organism has been identified. Seen a couple of other cases pop up in the past two weeks. Some feel it is some type of mild pathogen that shows symptoms when some other stress induces them. If it is in a commercial planting, it would probably be best to remove the plant. I have seen it disappear or appear in the same vine only every two or three years. Most people get fed up with it and pull the damned thing and replace it. Not soil borne, so replanting is definately an option.

The other possibility is that it is caused by solvent or petroleum toxicity. Gasoline leak, oil change, etc can give the same type of leaf burn.

Jim Kamas
Extension Horticulturist
Fredericksburg, Texas