"Enduring tree symbol" has evolved over centuries

The Christmas tree remains a powerful symbol for many, evoking emotions that can be traced through thousands of years of humankind and across many faiths.

"Christmas trees probably add more to mark the period of 'peace on earth, goodwill toward men' than any other product of the soil," says Ann Kirk-Davis, whose family has been raising and selling Christmas trees for generations.

"This enduring tree symbol — which is even older than Christianity and not exclusive to any one religion — remains a firmly established part of our holiday customs, engaging not only our senses of sight, touch and smell but also our sense of tradition," Kirk-Davis said.

The Christmas tree has evolved from centuries-old traditions.

JOE RAEDLE / GETTY IMAGES The 81st National Christmas Tree, a 40-foot Colorado blue spruce, is lit on the Ellipse in front of the White House during the Dec. 2 Christmas Pageant of Peace.

In the seventh century in Germany, St. Boniface used the tree's triangular shape to symbolize the Holy Trinity. In the Middle Ages, evergreens were decorated with red apples to mark the pagan festival of Adam and Eve.

In Latvia in 1510, Martin Luther, inspired by the stars shimmering through the trees as he walked through the woods one night, cut down a small tree, took it home and decorated it with candles for his children.

One of the first documented reports of Christmas trees in America was in 1747 among the German Moravian immigrants in Bethlehem, Pa. In 1825, the Saturday Evening Post noted the decorated trees in Philadelphia, and in 1842 candles, popcorn, nuts and homemade paper ornaments were used to decorate Christmas trees in Williamsburg, Va.

By 1900, one in five American families had a Christmas tree, and over the next 20 years, the popularity of Christmas trees spread rapidly. Americans now buy about 25 million trees each December, though that number has been decreasing as aging baby boomers use artificial trees or don't put up a tree at all.

About seven of 10 households have an artificial tree, with many of today's models reasonably presentable and costing in the neighborhood of $200. For more than $1,000, you can get a faux tree — faux being more expensive than fake — with hundreds of lights embedded in branches, a pine scent and plastic needles to scatter on the floor.

Ninety-eight percent of all real trees are grown on plantations rather than cut from the wild.

Today's trees are fuller and better shaped, but it's not because of biotechnology or genetics. Instead, longtime Maine grower Doug Kell Sr. explains, farmers simply started "shearing" trees as they grew — using a knife to trim branches. The result: a more perfect cone shape with fewer bare spots.

Most trees come from Oregon, Michigan, North Carolina, Washington, Wisconsin and California. Among the most popular species are Scotch pine, Douglas fir, white pine, balsam fir and white spruce. The most expensive are the Noble fir on the West Coast and the Fraser fir on the East Coast, known for holding their needles, scent and color.

Charlie Grogan, president of the growers' National Christmas Tree Association, says the typical tree retails for about $40.