I had this message from Jeff who has given me permission to share. It's a very clear message with his thoughts on how I worked the tree. Thanks, Jeff.
He's got it partly right and I would welcome any further suggestions but will only 'blog' them with permission!!!
"Since no one has posted how they think you did the pin, I'll try.
Starting at the top, you did a series of split rings with beads in the centres and long picots on both sides in which beads can be threaded onto. Next, you start a chain along the bottom (which will continue around), joining to the long beaded picots. Along the chain, you add beads that are a) on the shuttle 2 thread and b) threaded onto picots that are joined back to (similar the TIAS lady) at the widest part of the tree. Once at the top, you join into the star button, and continue back down the other side, again joining to the long picots of the centre split rings. Once you are back at the beginning of the chain, you add the beads that become the trunk of the tree, either just threaded onto the ends of your threads before finishing or joined on in some other
fashion (I can't really tell how exactly). I'm pretty sure I see a knot at the top of the trunk so I know you ended there.
Hopefully you can understand what I'm trying to say. I'm not sure (obviously!) if this is how you did it, but that's how I would tackle this project. If thats not how you did it, I look forward to hearing your method.
Jeff"