Question
Hello Ronald,

Here in Ohio the weather has been very dry lately and I've noticed the last few times I've mowed the lawn that a fine black "powder" accumulates on top of the riding mower deck. I'm told this may be a mold or fungus that lays on the lawn surface and is common with the very dry conditions. Is this correct?

Thanks,
David

Answer
I have seen the same signs on grasses infected with smut disease but not on lawns. Maybe a smut infection is present. Smut diseases are difficult to control. Resistant varieties are the answer. Alternatively, it may be sooty mold but there has to be some kind of insect activity beforehand. The insect secretes honeydew which attracts ants in the first place and later comes this black fungus to feed on any residue on the leaf surface.
Hopefully, this is of some help to you.