Here's the one I made.
It's bigger than I thought it would be so more a doily than a tree decoration. I used Anchor crochet cotton #12. It took only a few hours to make but there are no written instructions just a chart. The chart was however very clear and matched exactly to the size of my work.
I will make more of these - but probably next year - the other designs are just as pretty. In a thicker yarn, maybe 4ply cotton, they would make lovely place mats for the Christmas table.