In a parallel universe

THE TREES EVEN HAVE LITTLE LEGS, A PARALLEL UNIVERSE INDEED

But their present is in a box, that means they package things in their own skin.... Oh that's NASTY

Woulden't the human still have skin on it just like the trees still have needles? They would probably only take down the human tree when the flesh started to rot off, just like some of us are too lazy to take down our Christmas trees before they start to die.