The tradition of harvesting your own Christmas tree - cemented in the collective American memory thanks to Currier & Ives and Norman Rockwell and, yes, even Chevy Chase - may be fading.

Last year, 16 percent of the nation’s 31.3 million live Christmas trees were cut by the people whose family rooms they’d grace, according to industry data. A larger percentage, about one in four, were bought at big-box chains.