Close-up of the spines of a jumping cholla, Cylindropuntia fulgida (tentative ID)
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Ponce de Leon Drive, Catalina foothills, Tucson, Arizona
December 20, 2012 (morning)
Jumping cholla or glowing cholla, Cylindropuntia fulgida (tentative ID)
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Ponce de Leon Drive, Catalina foothills, Tucson, Arizona
December 20, 2012 (morning)
Desert mistletoe, Phoradendron californicum.
We saw it everywhere, growing on pretty much every kind of desert tree, shrub, even cactus.
Of it, Wikipedia says:  the desert mistletoe or mesquite mistletoe, is a parasitic plant native to southern California, Nevada, Arizona, and Baja California. It can be found in the Mojave and Sonoran Deserts under 4000 feet elevation.

The female plants produce the berries, which can be white, pink, red, or orange as seen here.  Leaves are little more than scales along the branches.
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Ponce de Leon Drive, Catalina foothills, Tucson, Arizona
December 20, 2012 (morning)
Desert mistletoe seen growing on a shrub adjacent to a staghorn (or buckhorn) cholla.
You can see a few of the bare branches of the shrub emerging from the mistletoe mass, and on one near the center of the shot you see some wicked looking downward curving spines.
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Ponce de Leon Drive, Catalina foothills, Tucson, Arizona
December 20, 2012 (morning)
Saguaro detail.
Virtually every mature saguaro bears 'scars' of some environmental insults or attacks.  They're kind of the cactus equivalent of wrinkles, I guess.
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Ponce de Leon Drive, Catalina foothills, Tucson, Arizona
December 20, 2012 (morning)
See photo in original gallery.