Organ Pipe Cactus National Monument
Two spectacular Mexican cacti live in a small corner of southern Arizona and nowhere else in the U.S.
Organ Pipe Cactus - Stenocereus thurberi:  Also found a few miles north and east of the monument.
Senita Cactus - Lophocereus schottii:  Restricted to Senita Basin within the monument.
The road into Senita Basin is now closed to vehicles, but several trails provide access to hikers.
UPDATED 01/26/05

Three Giant Columnar Cacti
Senita (foreground), Organ Pipe (right), Saguaro (left).

Senita Cactus  Lophocereus schottii

Senita:  Spines at the top of the column are dense, bristly, and relatively soft.  The other spines are clusters of small but stout spikes.

Organ Pipe Cactus  Stenocereus thurberi
Fragile spines on black areoles.  Weathered dead wood.  Rare crested branch.

Aging palo verde nurse tree with Organ Pipe (L) and Saguaro (R).

Cactus Forest:  Senita, Organ Pipe, and Saguaro.

SENITA 3-D Anaglyph Photo
ORGAN PIPE 3-D Anaglyph Photo
Arizona Rare Cactus Photos