I added in one more fabric. It's a pale brown with a touch of rust and green. It works well with the others. but it's only there in small amounts.
I started auditioning Stems/Trunks.
I'll try a few more and a few different arrangements of both the circles and the stems.
I've also been considering ornamentation for the "trees" but I haven't worked that one out yet.
Step by step!