WASHINGTON – It takes a while for a tree to be green.
For decades, the National Christmas Tree was heartily chopped down from forests throughout the nation and trucked to the White House to be decked out in lights and ornaments. Then someone finally had the idea to plant the tree, so it would grow each year; the current tree has stood in place for 28 years.
On Thursday, the blue spruce passed an ecological milestone. When President Bush flicked the switch, those were not filament-burning bulbs that bedazzled the thousands who thronged the Ellipse for the annual tradition; they were glowing, energy-efficient light-emitting diodes.
It was a first for the national tree and part of a new holiday tradition as public Christmas displays switch to bulbs that illuminate by chemical reaction.
The LEDs have become available commercially for residential use only in the past year or two, but retailers report a steady increase in sales. The lights offer lots of advantages beyond significant energy savings. Although slightly more expensive to purchase, they can be made in a rainbow of colors and last much longer than old-fashioned lights.
Of course, this all means an end to some other Christmas traditions, such as decorating the tree, plugging in the lights and standing back to discover that one strand, way near the top, is out.
Or the merriment of burnt fingers from grabbing hot lights. Or the comfort and joy of blown fuses from overloaded circuits.
LEDs are cool to the touch and generally use about 10 percent of the energy of a standard incandescent bulb. They’re also nearly indestructible.
Traditional lights burn white and get their color from filters. But LEDs are created out of semiconductors; changing their composition changes their color, across the spectrum from blue to red, said Nadarajah Narendran, director of research at the Lighting Research Center in Troy, N.Y. They don’t heat up. Instead, the atoms have charges that combine and release light.
Thursday at the White House, just before 6 p.m. 20,280 LEDs, each bulb about the size of a fingertip, clicked on to applause from the crowd.
Some spectators had heard of plans to light the tree with LEDs, and several said the lighting was as good as ever.
“It looks great,” said Rod Rosenboom, visiting from Parrish, Fla. Noting the extended life of LEDs, he said, “You can pass them on to your kids.”