Tree Bark With Lichens

The inspiration:

I pulled out quite a wide range of colours:
A 30 x 22 stitch repeat:Carefully plotted so that all four sides line up thus:
I envision pulling colours from the palette above, and arranging them in random stripes , with the pattern in a deep chocolate brown or even a charcoal gray. Then again, a suitably hued handpaint would also make a lovely background. In the original photo, I love the way the little bits of buttery yellow lichen on the bark make the rest of the colour scheme pop - I would be tempted to duplicate stitch a few spots here and there for effect.