When September comes to Hamtramck the sidewalks fill with kids again and St. Florian's spire keeps its usual watch over the rooftops. The Lawn Academy is out through all of it, mowing, trimming and edging yards that have taken a whole summer of sun, sneakers and folding chairs. Fall is the honest season for grass in this city — cooler nights, deeper color, and cleanups that lift the leaves before they mat down over the turf. There is real pleasure in the last cuts of the year, when the lines hold crisp for a week instead of three days. Lawn care on a steady schedule, from the first thaw to the final leaf.