By November the salt marsh of the Timucuan Preserve has turned from summer green to bronze, and on a cool morning the tide slips out through the creeks, leaving the mudflats shining and the egrets stalking their edges. Green Earth Solutions Inc does lawn care in a city with that much living ground at its doorstep, where the sand under a front lawn is kin to the shoreline a short drive away. Late autumn is a turning point for turf here: the heat breaks, growth eases, and a lawn finally has room to breathe after the long summer. Regular mowing and trimming through these weeks leave a yard in good shape for the mild months ahead. It is a promising sort of work — earth tended with care, grass holding its green while the marsh beyond the city wears its autumn copper.