I don't think I've ever seen a barn or shed painted green before, but this one is a lovely shade of green and looks very nice in the spot where it stands. With the way the doors are constructed, this might, indeed, be more of a shed than a barn, but its size and method of construction look more like a single-story barn than a shed which is why I decided to catalog it in my collection.
There is also a small structure at the front right-corner, which might be a housing for a well pump, supplying water to the house nearby. Or, it might be a doghouse. Or even something else, entirely... the possibilities with these structures are endless.
As with so many barns in this area, much undeveloped land is nearby as can be seen by the wooded areas in the following aerial photo from BING Maps:
The rural nature of this area is also evidenced by a small side-road nearby, labeled on the map as Bovine Lane 🐮