How to dispose of Christmas trees in Denmark / Christmas trees on the menu at Berlin Zoo / The Christmas tree debate: 'If I take it away, I might as well call the whole thing off...' / Christmas tree collection: How to get rid of your real festive tree / Forget the Christmas tree cluster - It's all about the cosmic grinch this year / Christmas trees in Germany were decorated with apples instead of ornaments in the 1600s for 'Adam and Eve Day' / 8 plants that look similar to Christmas trees / From Germany to glitter: The surprising root of Christmas trees / What's putting Christmas trees at risk? Try this week's Global News quiz / The Christmas festival where every tree tells a story