If you look closely at the work-in-progess photos taken at this summer's Wild Arts Walk/Quick Draw gig, you'll see the birth of this particular panel taking place. As mentioned elsewhere at length, there actually is some prepwork done behind the scenes for the event, and well in advance of sitting down to the challenge I'll test the waters by doing a dry run beforehand. The logistics of such a timed endeavor preclude any protracted musings over material, and excepting any on-the-spot adaptations from unplanned accidents, there's little if any spontaneity aside from the spontaneous combustion that occurs internally.
Here's both the test panel, sans iconic wildflower, and below is the original doodle done in the sketchbook, including a nice, warm wash done by dipping the brush in a mocha. Mmmm... art.