Another Vespula ground yellowjacket species in the ‘hood! Southern Yellowjacket, Vespula squamosa. This is a queen. She was probably looking for a nice hole at the base of this old cherry to start a nest. This is the first report for this species in Brooklyn on iNaturalist; they’re recorded on Staten Island, Manhattan, and further out on Long Island. That makes five Vespula species I’ve seen here in the borough.
Backyard and Beyond 
Wow, good for them!! How did you determine she is the queen? Were you able to see her size in comparison to her other wasps? I am a honey beekeeper and this is why I ask. My first thought was how often have “you” seen this species & are able to ID a queen, especially if she was solitaire when you spotted her, etc….
I suspected because of behavior, the poking around the tree base, similar to other Vespula species queens seen in spring time. A couple people on iNaturalist confirmed the ID. Vespula queens have different markings from the workers and the males. Bugguide has a nice picture key to the North American species https://bugguide.net/node/view/554