I have been a bit slack about the black line drawing I wrote about a while ago. Even though I really enjoyed it and had this (sort of) resolution to do some every week, I haven't done any recently, till the last few days.
I am still working on my bark images and trying to utilise them in my drawing - partly because I have plenty of images of tree trunks to use.
However, I have come across references to zen doodling, zen drawing and zentangles (which seems to be a trademark of the same idea as the other two). There is a whole lot of chatter on the internet about the meditative elements of this doodle drawing. The recommended way to do it is more freeform than I have been doing but there is a definite similarity.
I also came across an article by Laura Wasilowski in Quilting Arts magazine about zen doodling for designing quilts. It has colour in it rather than the black and white of the zen doodling that I have seen online. It takes the idea in a slightly different direction, one I don't want to follow at the moment. But it is worth keeping in mind.