Just when you thought stencils, rulers, triangles and protractors went extinct back with the dinosaurs, along comes someone to transform them into digital illustration tools. Virtual stencils, virtual pens… but real results.
First, you draw a black and white image in an illustration app. The black parts will fill with color; the white will be masked. Export the illustration.
Import the illustration into Morpholio Trace as a new stencil, run some colored pens over it, then trace around it in black so it looks hand drawn. Copy the trees as needed
Voilà! You have something that looks like what I did in 1989, only faster and much easier to share.