Morning fog sits in the Harlem Valley long after the ridges are lit, pooling white over the Swamp River meadows. 3 Hermanos Landscaping starts the day inside it, mowing Dover yards while the grass is still cool and the cut comes off clean. The trimming goes tight to fence rails, the mailbox post, the base of every old sugar maple. By the time the valley burns off, another lawn is standing up striped and squared away. Straightforward lawn care, done at the hour Dover looks its best.