What caused the blotch on this leaf? I’m pretty sure that whatever it was, it was just pursuing its own nutrition or some other such necessity, not setting out to create beauty. But it is beautiful.

I knew I’d be waiting for an hour or more for a car repair today, so I brought this work-in-progress along. I took a walk and then stopped at a cafe to draw; it is now closed, and I am hoping the car will be ready before they tell me I have to leave.