It is an unlikely battleground. It is an even less likely corner of Flushing Meadows-Corona Park in Queens.

If the blacktop were hot enough in the 31-acre, 6,640-space parking lot outside Citi Field, along Roosevelt Avenue, you might be able to grill a hamburger on it. But the tender young trees lining the pedestrian walkways would scarcely offer much shade for your picnic.

Because it is parkland, however, the Appellate Division of State Supreme Court ruled last week that it could not be taken as a development site for a one-million-square-foot shopping mall simply because the administration of former Mayor Michael R. Bloomberg said it could.

The court’s decision brings a halt — at least temporarily — to what has seemed like the relentless commercial appropriation of public land in New York City, often under the rationale that private profit is the only way the people can have nice things.