Environment: Week's Watch

Now that the holiday season is over, what should be done with old Christmas trees? Henry L. Diamond, New York State's commissioner of environmental conservation, last week warned that burning them causes air pollution and burying them whole wastes scarce landfill areas. As a better ecological idea, Diamond singled out the system used in Greenburgh, N.Y. The town is picking up the trees at curbside and running them through chipping machines, used the rest of the year to clean up after tree prunings on the town's property. The tiny chips can then be used as a compact landfill or as a...