take a sprig to your local Agritcultrual Extension service. They will also know if the problem is common in the area.
Also look for bugs on the plant and vole holes on the ground.
1/8/09 "Only government can provide the short-term boost necessary to lift us from a recession this deep and severe."
1/28/09 "In the end, the answer to our economic troubles rests less in my hands or in the hands of our legislators than it does with America's workers and the businesses that employ them."