Saturday morning on the side streets of West Babylon sounds like a dozen mowers finding their rhythm at once. Donnell Lawn Care LLC is one of them, working through the capes and ranches with mowing, string trimming, edging and the cleanups that bookend the year. The lots here are modest and the standards are not; a strip of grass beside a driveway still deserves a straight edge. There is a particular pleasure in the last pass, when the stripes line up and every clipping is gone. Then it is on to the next yard, and the block gets a little sharper.