This is what remains of a dead saguaro cactus in Papago Park in Phoenix, Arizona. Originally a color image, I converted to black and white using Silver Efex Pro 2 from Nik software. Very simple to do from Photoshop with lots of built in presets to achieve any desired effect.
This image took an honorable mention in a 2011 Northern Virginia Photographic Society monthly competition.
Location: N33 27 21.87 W111 56 45.30