Storms reach Oakland County sideways sometimes — a clipper dropping down out of Canada that leaves three inches and a wind that packs every one of them into the corners. Alan Mango Lawn & Snow Services works that shift: plowing drives, cutting walks and steps down to concrete, and putting salt where the afternoon melt will only refreeze by dark. Southfield's side streets glaze fast after a January thaw, and the difference between a slick apron and a safe one is simply somebody who came out. The trucks move while the city sleeps, block to block, so the first car of the morning never has to guess at the footing. Snow work, done for the neighborhoods pressed close around this city.