The Middlesex Greenway carries its old rail line straight through the borough — green and humming with bicycles in June, a quiet white ribbon in January. DCR Companies Inc. keeps both of those seasons on the books. Warm months: mowing, edging, trimming, mulch in the beds, seed on the tired patches, and the cleanups that open and close the year. Cold months: plow trucks on driveways and lots, shovels on the walks, salt on the north-facing steps that stay frozen all day long. One company handling the whole twelve months rather than half of them, which is how a property keeps looking like somebody is in charge of it.