Grand Army Plaza Wilderness

 There are two sort of abandoned green spaces as someone approaches Grand Army Plaza from Flatbush Avenue from the west.  It looks really cool inside.

I'm pretty sure that the Parks Department is responsible for it (or somebody is, at any rate), because of this lock.

There are mulberry trees there, but they don't look like they were planted deliberately.

Here's a close up of the roots that make that clear.

This half of the green space has a stature of Alexander Skene