If the stump is still there you can have it removed.
Mushrooms growing on roof.
If it s gone just keep the area well raked and aerated to improve drainage.
The mushrooms are growing on my rental house not many only a small side of the house but persistent over the 3 years in small quantity since i ve owned this rental.
I haven t panicked because the moisture meter shows nothing on the opposite drywall side but it s obvious the siding is getting damp to the point of growing mushrooms.
If you have an area where a tree used to stand even if the stump is gone the dead roots underground may encourage mushroom growth.
It may be from a plumbing leak a roof leak or a severe lack of ventilation.
Correcting the moisture problem is the first step in the eradication procedure.
It s a combination of algae and fungus and usually has a light mint green color.
It doesn t trap as much water against the surface of the roof as moss but it can be acidic and has strands that can penetrate into the shingles.
In this situation first the leak must be fixed and secondly the roof must be treated also in order to successfully kill the root of the infestation.
It s not unusual to see mushrooms growing in the basement that derive their moisture from a rooftop leak.
Mushrooms in the house mushrooms growing indoors present a classic sign of a moisture problem.
Leaks have ruined equipment created mold issues and fungus.
From your description you may have lichen growing on the surface of your roof.