http://id.mind.net/~zona/mmts/geometrySection/fractals/tree/treeFractal.html

Golden TreeWinchester 15 August 2002A year later, the Circlemakers produced a different kind of binary fission, and this time it had a two to the fourth (24) motif: a tree with four steps of branching, having 16 fruits.It branched at one-third angles (120°) and its branch-lengths made golden ratios. A reconstruction of this 'golden tree' by Allan Brown is here shown, containing about 20 iterations. Does its boundary resemble that of the formation? The different branches grow to just touch each other, and it is only the phi-ratio which does this: no wonder Mother Nature likes using it (The Golden Ratio, Mario Livio, 2002).

http://www.hypermaths.org/cropcircles/chapter2/index.html