Dead Green Man

This piece of landscaping has long caught my eye.  The householder has recently tried turfing over the bed, but only got so far (I'm guessing it's too late in the year to turf).  Now it looks like this.
Previously, in rain, it turned into a tan pond.
Once, it contained a tree of some sort: the trunk is razed to mud(ground) level.  Probably a cherry - as usual.