Saguaro detail.
In this shot, it was the shadow of one rib, cast by the early morning light onto the neighboring rib, that appealed especially to me.
Close inspection of the shot revealed to me (seen best on the left-most rib) that many of the spines appear double.  I believe, in fact, that most if not all of those 'double' spines are the result of the original spine splitting.
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Ponce de Leon Drive, Catalina foothills, Tucson, Arizona
December 20, 2012 (morning)
Welcome to Tucson this saguaro seemed to be saying.
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Ponce de Leon Drive, Catalina foothills, Tucson, Arizona
December 20, 2012 (morning)
Deep blue sky and a dark rocky butte offset flowering cactus beauty.
Cactus at Lake Powell
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Cactus Sedona
Saguaro Sunset
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See photo in original gallery.