The act of blowing ones nose without the standard required receptacle of choice- a tissue or kleenex. Using one finger, block one nostril, aiming unblocked nostril away from body blow hard through that nostril, discharging boogers onto the gound or nearest bush. Repeat action for other nostril.
Typically used in the Australian outback where tissues/kleenex are often not readily available.
Wazza was driving across the Nullabor, had a crusty booger up his nose that he couldn't reach with his fat fingers, and he couldn't find his hanky. So, he wound down his window, aimed out of the car and had a bushy blow instead.