Each year, tens of millions of trees are chopped down, placed in living rooms around the world and decorated in time for Christmas. A few weeks later, once the festivities are over (and the trees are looking a little worse for wear), most are tossed out.

On the other hand, a plastic tree can be bought once, and be re-used year after year (depending on how long it lasts). So, which option is actually better for the environment?