Q.Grapevine
I have a grapevine that’s at least 50 years old. Each spring it blooms and produces an abundance of grapes. This sprin it bloomed as usual, and the as if overnight, I noticed the leaves wilting and eventually dry up. Not all the branches from the main trunk look dead. The leaves don’t appear to have any disease growing on them. Should I cut off the dead branches, and hope the vine regenerates itself?
Though you many not be able to see any disease, I would suggest spraying with a general purpose fruit spray.
There are several diseases that could cause leaf wilt and die off.
These links will help you pinpoint the issue.
http://www.ct.gov/caes/lib/caes/documents/publications/fact_sheets/plant_pathology_and_ecology/disease_control_for_home_grape_plantings.pdf
http://www.ipm.msu.edu/grape_diseases