Cactus Flowers
Northern Mockingbird (tentative ID) perched on ocotillo stems.
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Saguaro National Park, East.
Tucson, Arizona
December 20, 2012 (mid- to late morning)
Impression of the Sonoran desert - conventional treatment of a wider view.
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Saguaro National Park, East.
Tucson, Arizona
December 20, 2012 (mid- to late morning)
Impression of the Sonoran desert - filtered treatment in portrait format.

Taken from the roadside, possibly even from the moving car.  The original was a flat, poorly focused image.  The angle of the light relative to our position, for one thing, and the time of day, for another, weren't conducive to a great shot.  But I liked the two large saguaros when I saw them, and I still like the overall composition of the shot.  So I fell back on pp'ing with some filters to make the image pop a little more and to make it obvious that I was going for an impression of the scene rather than a strict rendering of it.
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Saguaro National Park, East.
Tucson, Arizona
December 20, 2012 (mid- to late morning)
(For anyone interested, I used about equal amounts of the Photoshop Fresco and Sumi-e filters.)
Javelina Rocks

DP021-2013.  Posted January 21, 2013; processed Jan. 21.
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The location name, Javelina Rocks, describes an outcropping of Catalina gneiss that is frequented by javelinas.  The last major turnout on the park's loop drive is at this spot.  The gneiss in question formed from granite rather than from sedimentary rock.  Bright neon green lichen had colonized many of the surfaces.  I don't yet know the geologic history that tipped the layers of rock so steeply at this location.
Saguaro National Park, East.
Tucson, Arizona
December 20, 2012 (mid- to late morning)

Many thanks to all who left comments on the euphorbia picture, especially those who looked at both versions and expressed a preference one way or another.
NM-2013-111: Soledad Canyon, Dona Ana County, NM, USA
Cactus
Cactus Flowers
Cactus Flowers
Cactus Flowers
See photo in original gallery.