I think it's linked to the state of Arizona in the USA. The cactus,sunset and lightning bolts have been associated with that state, as was the swastika (a native American symbol) that was used as an emblem of the state in the 1930's on various municipal buildings and seen on Department of Transportation Highway signs until a certain European gentleman decided to use it for his own ends.....
'I do not think we can hope for any better thing now.
We shall stick it out to the end, but we are getting weaker of course, and the end cannot be far.
It seems a pity, but I do not think I can write more. R. SCOTT.
Last Entry - For God's sake look after our people.'
In memory of Capt. Robert Falcon Scott, Edward Wilson, Henry Bowers, Lawrence Oates and Edgar Evans. South Pole Expedition, 30th March 1912.