I live in the Frederick County Watershed and this last year have noticed tiny black dots appear on my vehicle, bird feeders, and other areas surrounding our house. I've read that it is most likely Artillery Fungus. Is there anything that will help get all these spots off my car? I've scrapped some of them off but it still leaves a black spot. Also is there anyway to prevent it from continuing to grow and spread?
Artillery fungus shoots its spores in a globule which are the black dots you see. The fungus has to live on decaying organic matter, and these days it is usually the mulch we've spread around our house. The spores may have come into the landscape on a load of mulch.
If you have mulch, you may want to remove it and replace with clean mulch. If only a little mulch is left, you can cover it with clean mulch (though that takes the chance that spores will remain under the new mulch.)
Removing the spots is difficult, as you know. People have had success with cleaning by soaking them thoroughly, letting them sit while wet, then scrubbing off the spots. You don't want the globules to wash onto fresh mulch. Wait to put down new mulch until you finished cleaning. Clean on an overcast, not windy, day.
Here's more info:https://extension.psu.edu/what-is-growing-in-my-landscape-mulch-mushrooms-slime-molds-and-fungus