Bacterial Black Stalk is caused by the same bacterium that causes Hollow Stalk (Erwinia sp) and is favored by the same
conditions.  Tobacco with excessive nitrogen and which has been exposed to wet/rainy conditions are more vulnerable.
Black Stalk doesn't always rot the pith of the stalk but will cause black streaks along the stalk and may cause leaf drop as
leaf axils develop the rot.  Little can be done to prevent black stalk other than keeping nitrogen at a reasonable level.  Taking
damaged plants to the barn can increase the chances of barn rot and further damage.