Can you get a picture?
Are they real small like dots? Sticky?
There are several scenarios. Here is one, that may actualy be your problem. No pic, or better description. So I am just guessing.
Sooty Mold. Generaly dark to almost black but have seen it in lighter colors. Aphids that suck the sap from a plant will discharge a sticky residue. What will then happen is dust and polutents will stick to the residue.
Please provide more info of your problem
Are they real small like dots? Sticky?
There are several scenarios. Here is one, that may actualy be your problem. No pic, or better description. So I am just guessing.
Sooty Mold. Generaly dark to almost black but have seen it in lighter colors. Aphids that suck the sap from a plant will discharge a sticky residue. What will then happen is dust and polutents will stick to the residue.
Please provide more info of your problem
