A convoy of semi-trailer trucks left Columbia Falls, Maine, last weekend on its way to Arlington National Cemetery, where volunteers will honor veterans in a wreath-laying ceremony, known as Wreaths Across America Day, this Saturday, December 13.The annual event depends on volunteers, and the trucking industry is a major player in those efforts. This year, 400 transportation companies and more than 1,200 drivers have volunteered to “move the mission,” which includes the more than one-mile-long convoy from Maine to Arlington, Va., as well as individual trucks that will pick up loads of wreaths and deliver them to cemeteries across the country.All told, truckers will move 800 loads of wreaths from Maine to nearly 5,600 locations this Wreaths Across American Day, which is sponsored by the non-profit organization Wreaths Across America (WAA).WAA dates back to 1992, when Morrill Worcester, owner of Harrington, Maine-based Worcester Wreath Co., delivered a load of 5,000 surplus wreaths to Arlington National Cemetery to honor veterans. Today, Worcester and his wife, Karen, oversee efforts to deliver millions of wreaths each year—3.1 million wreaths will be placed this Saturday. The couple also takes part in the convoy’s “Escort to Arlington,” which makes four stops a day on its weeklong trek to Virginia, honoring veterans and thanking volunteers—especially the truckers.“[Wreaths Across America] does not exist without the trucking industry. Period,” Karen Worcester, who is also WAA’s executive director, told attendees at a convoy stop in Massachusetts Tuesday. “The drivers and the companies are the best ambassadors we have. We…