This is the end result of the peartree saga posted on this blog.
I'll post some photos of the process next week. It involved:
re-biting the plate to darken some thick lines
covering it in nice poisonous powdered pine sap (called rosin), and nearly getting covered in it myself
trying not to set fire to the studio with a gas jet to melt the rosin
covering it in thick gooey varnish in different stages, to get the different dark areas.
cleaning it with meths, which turns my stomach a bit.
Over all, great fun!