Folding wooden Christmas tree

There was a spate of these last year which seemed to turn it from a novelty to a commonplace. As so often, I didn't get round to making one, but there is a fresh chance every year.
There seem to be three broad options:

• plywood
• solid wood (this was how it started)
• 'driftwood': the rustic look, though this would go against one major advantage of the scheme - the ability to store flat.

If you opt for rustic, the materials more-or-less dictate the construction method. 

Otherwise there are two main design decisions: 1. single or multiple branches; 2. separation.

Image sources:
plywood - inhabitat /  onetwotree
solid wood - monoqi
driftwood - pinterest

solid, single branched, dowelling separators

Plywood,
double branched,
plywood separators

driftwood / twigs (small)