Murphyette,
Does this mean that whole section of yard is forever at the mercy of a mushroom attack?
It's hard to say, but my guess would be, each year they would come back smaller and smaller amounts as the wood render's down...
I had them in front again, but not nearly as much as the year before, I assume for the coming years ahead too....
But if you wanted to dig up the area, move it to the composting area, would be your choice...
Sounds like alot of work, but if you need the area???? Up to you????
None that I know of??? But, not sure.
If you're not doing anything with the area, leave it be, natures at work...I'm the type to let it go, I like to look at them, so many different shapes.. We had white pine needles pile and had some quite interesting ones this beginning of summer, really neat.
Weezie