By January the Bermuda has gone straw-gold and the hardwoods stand bare, and for a few weeks you can finally see the shape of a yard — the grade, the bones of the beds, the long ridge the city was built along running off through the pines. Atlanta Landscape Co. LLC likes this season for the structural work: shrubs pruned back, bed borders re-cut, mulch laid down while the ground is quiet. Come March the mowing begins again and hardly stops until the leaves are down. Between those two poles, a property gets its posture back. It is ordinary work, and the difference it makes is not.