On a July evening the bandstand on Townsend Common throws a long shadow across grass that somebody kept short all summer. BLB Property Maintenance, Inc. does that kind of keeping for yards around town: mowing, string trimming, edging, and the seasonal cleanups at either end of the year. The work rewards repetition — same day, same height, the same clean border along the drive. When October comes the leaves arrive in one loud week and get hauled off while they are still dry enough to move. Townsend looks its best when nobody notices the maintenance at all.