A Brooklyn lawn is often twenty feet of green held tight between two fences, and it still deserves a straight line. SRG Landscaping LLC keeps the backyards near the Gowanus in order — mowing, edging along the flagstones, cutting back whatever leans over from next door, and carrying the spring and fall debris out through a side gate barely wider than a wheelbarrow. On a June evening the light drops slantwise between the row houses and every mown strip shows up like corduroy. Fresh mulch goes dark around the beds, the clippings leave with the truck, and the little square reads finished. It is close work done with the neighbors' windows open, and it gets done tidily.