[Illustration: Lemaireocereus thurberi
Lophocereus schotti]
Common names: ORGANPIPE CACTUS, SINITA; (_PITAHAYA DULCE_)
Arizona desert: (_Lemaireocereus thurberi_). Pink lavender. May-June.
Arizona desert: (_Lophocereus schotti_). Pink. April-August.
Cactus family. Size: In clumps, stems up to 15 feet.
Two somewhat similar, columnar cacti occur in the United States only in
Organ Pipe Cactus National Monument and in its immediate vicinity. Both
are fairly common in northwestern Mexico.
These two spectacular desert giants with their clumps of erect branches
are sufficiently similar to be readily confused at first glance.
However, the stems of the Organpipe (_L. thurberi_) are longer and
contain more but much smaller ridges than do the stems of the Sinita or
“Whisker cactus.” The name “Sinita” (meaning old age) refers to the
long, gray, hair-like spines covering the upper ends of the Sinita
stems.
Both species are night-blooming, the flowers, which appear along the
sides and at the tips of the stems, closing soon after sunrise the
following morning. Fruits of the Organpipe are harvested by the Papago
Indians.
Although these two species of cactus are restricted to a very limited
area, they are sufficiently spectacular and interesting to be considered
worthy of inclusion in this booklet. It was to protect these species,
threatened with extinction in the United States, and other rare and
interesting forms of desert plants and animals, that Organ Pipe Cactus
National Monument was established.