Upstream on the Black River the water goes still and tea-colored, herons standing in the shallows while the morning fog burns off the banks. J&R Lawn Service LLC starts its June days in that kind of quiet, mower loaded, dew still heavy enough to darken your boots. The work is straightforward and done thoroughly: mowing on a regular cycle, trimming what the deck cannot reach, edging so every border reads clean. Cleanups take away the clippings and whatever the last storm shook loose. Port Huron summers are short and green and generous, and a lawn kept on schedule makes the most of every week of it.