On a July evening in North Brunswick Township the sprinklers come on street by street and the whole place smells like wet grass and warm asphalt. United Lawn Maintenance LLC has usually finished by then — the day's mowing done, fence lines trimmed, every walk and driveway edged and blown clean. The long straight blocks here make for long straight passes, and there is genuine pleasure in a row of lawns all cut to the same line. In April and November the work turns to cleanups, opening the beds and clearing the leaves away. Everything in between is the weekly visit, kept.