Late in the day the light on the backwater goes copper and a heron takes the long way home across the sand prairie. Verminators Wildlife Services spends hours like those on lawn work around Spring Lake, mowing, trimming the ragged corners, edging drives and walks until a yard has a border again. Grass on this sandy ground surges after rain and then sulks, so the schedule matters more than the muscle. By the end of the year the cleanups carry the leaves away, and the season with them. There is a plain pride in a yard that looks settled inside all that wild river country.