It gives me a seocnd career!
There may have been some real soil here at some point in the past, but bulldozers probably removed all that when the park was built.
I kept hoping that if I dug deep enough I would find sandy subsoil, but no. The clay is everywhere, and the only thing that chnages with depth is that the rocks get bitgger and more numerous.
I wish I had yards of free compost or manure (and teams of people with wheelbarrows to haul it)!