This evening’s lighting of the Rockefeller Center Christmas tree in New York City and tomorrow’s National Christmas Tree Lighting in Washington, D.C., reflect the increasingly green tenor of the times.

The Rockefeller Center tree was retrofitted in 2007 with energy-efficient LED lights powered partly by solar panels. For the National Christmas Tree, the 750 light strings and ornaments have been changed to LED lights, which are expected to trim electricity consumption this year from 18,000 watts to 6,000 watts. Our tests of LED holiday lights confirm that they’re not only more efficient but also safer than incandescent lights.

Unlike the Rockefeller Center tree, the federal government's tree is a live one. The 42-foot Colorado blue spruce was transplanted to the Ellipse between the White House and National Mall in 1978. (The U.S. Forest Service does allow people to cut holiday trees at 13 national forests. A $10 fee is required for each permit and only handsaws can be used. Other municipalities offer similar programs on their own public lands. Check with your town or county.)

Planting a live Christmas tree can provide long-term benefits to the environment and your property. See our tips on selecting, displaying, and replanting a live tree.­ If you have heavy tree cutting to do, use our free buyer’s guide to chain saws and follow our safety advice. Ratings of chain saws are available to subscribers.—Gian Trotta | e-mail | Twitter | Forums | Facebook

Essential information: For more seasonal news, branch out to the timely advice in our Holiday Shopping Guide. And stay safe this holiday season with this information for your tree, holiday lights, candles, and more and advice on fire extinguishers.