The Nature Conservancy's Cool Green Science blog on this -
To tree or not to tree?
We love trees. They clean our air and water, store our carbon, and lend a hand in creating many of life's needful things, from our homes and furniture to our beloved Louisville Sluggers. So we should never, ever cut one down for the sole purpose of decorating our living rooms for the month of December, right? Actually, wrong. If you choose a real Christmas tree over an artificial one, count yourself among the "greener" holiday makers.
Here's why: 30 million trees are harvested annually for Christmas, out of the 350-500 million growing on tree farms across the country. As each year's trees are harvested for sale, there are more than ten times as many left standing. A tradition of buying real trees keeps tree farms in business - and their lands covered in forest instead of development.
Conversely, about 10 million artificial trees are purchased each year. 90% are shipped to the U.S. from China. Artificial trees are not recyclable.
Want to make your already green choice even greener?
. Visit a cut-your-own tree farm instead of purchasing a pre-cut tree. That way, you'll know for certain that it wasn't shipped in from outside your home state.
. Use LED lights. Pass up the non-recyclable tinsel and make garland out of popcorn and/or cranberries.
. Keep using heirloom ornaments year after year, but if you're still looking to fill some space on the tree, you don't have to go the store-bought route. Try turning holiday cards or your child's artwork into ornaments. Or go for a walk to collect pine cones or seashells and decorate with glue and glitter.
. If you are planning to purchase ornaments, choose wooden ones over plastic. When you travel during the year, pick up a painted wood ornament from the destination you visit. Soon you'll have a collection of ornaments that bring back memories of trips with friends and family.
Another fun fact - UC Berkeley Forestry department’s annual Christmas tree sale sells thinned trees from the research forests in the Sierra Nevada -