From the U.S. Census Bureau:

The value of U.S. imports of Christmas tree ornaments from China between January and August 2009 was $470.3 million. China was the leading country of origin for such items. Similarly, China was the leading foreign source of artificial Christmas trees shipped to the United States ($28.6 million worth) during the same period.

Check out these statistics and more in our Facts for Features on the 2009 Holiday Season!
http://www.census.gov/Press-Release/www/releases/archives/facts_for_features_special_editions/014405.html