Quincy Center is a city yard game: a narrow strip of green behind the granite curb, a small square out back, tight corners around a fence and a bulkhead. Lawn care at that scale is close work — mowing, edging along the walks, trimming what the mower will never reach, then sweeping the trimmings off the sidewalk so the whole thing reads finished. On a midweek afternoon, with traffic running down Hancock Street and the shade off the old library stretching across the block, a modest lot can be made to look like somebody's clear idea of order. Small lawns are underrated; kept tight, they lift an entire street. That is the pleasure of doing this in the middle of a city.