Stop, back up.
Hey! Thats smoke!
Unclip, start stamping on the leaves and sure enough a couple were burning. I stuck around until I was sure it was out and I couldn't see smoke any more.
I don't know what caused it but I hope it wasn't a) deliberate or b) Some idiot throwing a still-lit cigarette butt out the window.
In case people haven't noticed Canberra is called the "bush capital", and like anywhere else in the bush isn't immune to bushfires.
I wonder if I should report this? And if so, to whom?