A barber works to the line, and N.Y. Lawn Barber L.L.C. takes its name seriously. Out in Jonesville, where the old hamlet sits at the crossroads and the maples throw long shade across the front yards, a lawn cut to an even height and edged tight along the walk reads like a fresh haircut. The week runs through the first hard flush of spring growth, the slow midsummer stretch when everything wants water, and the leaf-heavy afternoons of October. Mowing, trimming, edging, cleanup — small disciplines that add up to a yard with its shoulders back. Service runs through Clifton Park, Jonesville, Vischer Ferry, Rexford and Burnt Hills.