I have two hackberry trees in my front yard. This time of year, anything
under the hackberry trees are covered in a filthy black stain. Question
the black stuff?. Question #2....is there anything to do to
overcome the black stuff? such as a certain food or fertilizer additive.
I am in the Deep South, southwest of New Orleans.
It looks like mildew....but I don't think that's what it is.