This original idea seems to be a very old one already. Anyway, thanks to Laura from Sew Ritzy Tizy who spied this granny Christmas Tree in an old woman's house, I was also able to replicate such a sweet ornament. As the name has already given you a hint, it is realised from simple green granny squares with white borders. The baubles are simple sc or dc circles, and I also added a star (I used this free pattern) and a small string of sparkly yarn as a garland, to give it shine. I used a very small hook (1.1 mm) so my Christmas tree is only about 20 cm high.
PS: I just wanted to show you some goodies I just can't help adoring:
...and a little preview of the glittens I have made this weekend using this pattern - aren't they just lovely? :)