There is some form beginning to appear with a balance of dark across the painting. Just a little more to add, plus the highlights to some of the twigs. The very young twigs have a green tinge (yet to be added) and the more mature twigs are a deep red (Red Madder). The sun  lit parts of the twigs I shall add using a wash and I shall encourage the shadow part to 'bleed' into it which will give a feel of curve. The twigs in complete silhouette have a blue/violet bias.