By Phil Mercer
BBC News, Sydney
Australians have been urged to wear khaki on Friday, in memory of "Crocodile Hunter" Steve Irwin.
Irwin made khaki clothing his trademark
Leading political figures have joined the tribute for the naturalist and television personality who died this week after being struck by a stingray.
Throughout his energetic career, Steve Irwin was rarely seen in anything but his khaki-coloured shirts and shorts.
His legions of fans have been urged to wear the clothing out of respect for a man seen by many to have been an icon.
A national radio network has declared this "Crikey, It's Khaki Friday" - a reference to the crocodile hunter's famous catch-phrase.
A number of public figures, including the leader of the federal opposition, Kim Beazley, have joined in.
The khaki campaign began as a chain e-mail. It hopes to raise money for Steve Irwin's charity, Wildlife Warriors Worldwide.
Many Australians will remember him as a tireless conservationist.
"You know, everyone sort of loved his enthusiasm and his larger than life character, plus he did a lot of good things for the environment and the animals," one woman said.
Steve Irwin's family is planning a private funeral that may well take place next week.
A large public memorial service for the Australian television star is also being planned.
Steve Irwin died when he was struck through the heart by a stingray's barb when he was filming a wildlife documentary off the coast of Queensland.