Up on Billerica's ledge and gravel ground the soil runs thin, and a lawn there has to be coaxed rather than commanded. Peyman Landscape & Excavation LLC takes that as the good part of the job: mowing on a schedule the grass can actually keep, edges held true along drives cut out of hardpan, cleanups that leave beds bare and ready. October is the best of it — the maples letting go all at once, the crew moving through with rakes and blowers until the yard is a clean sheet again. Come April those same lawns wake up faster for having been stripped down in the fall. Billerica and the surrounding towns, mowing through to seasonal cleanup.