For numerous helpful suggestions, lists of common flowers, herbarium and
fresh specimens for use in preparing illustrations, and for assistance
in many other ways, the author and illustrator proffer sincere thanks to
the following: Glen Bean, L. Floyd Keller, Walter B. McDougall, and
William R. Supernaugh of the National Park Service; Dr. Norman C.
Cooper, research associate, Allen Hancock Foundation; Mrs. Robert Gibbs,
Isle Royale National Park, Mich.; Leslie M. Goodding, St. David,
Arizona; Edmund C. Jaeger, Riverside Junior College, California; Thomas
H. Kearney, California Academy of Sciences; Robert H. Peebles (who
kindly reviewed the manuscript), director of the U. S. Field Service
Station, Department of Agriculture, Sacaton, Arizona; Paul Ricker,
president, Wildflower Preservation Society, Washington, D. C.; and
Barton H. Warnock, head of biology department, Sul Ross State College,
Alpine, Texas.
[Illustration: Carnegiea gigantea]
Common Names: GIANT CACTUS, (SAGUARO)
Arizona desert. (_Carnegiea gigantea_). Waxy white. May-June.
Cactus family. Size: Up to 50 feet tall and 12 tons in weight.
Largest of the U. S. cacti, this species occurs only in southern and
western Arizona and adjoining northwestern Mexico and sparingly in
extreme southeast California. It is an indicator of the Sonoran Desert.
This giant is such a spectacular example of desert vegetation that it is
used as a trademark of the desert. It is the state flower of Arizona.
Blossoms unfold at night, remaining open until late the following
afternoon, attracting swarms of insects which in turn attract birds.
Fruits mature in July, resembling small, egg-shaped cucumbers. When
ripe, they burst open revealing a scarlet lining and deep red pulp
filled with tiny black seeds. Fruits are eagerly sought by birds and
rodents.
Because of its enormous capacity for storing water in its spongy stem
tissue, the Saguaro (sah-WAR-oh) produces flowers and fruits even during
droughts of long duration. When other foods failed, the Pima and Papago
Indians could depend upon the Saguaro harvest.
[Illustration: Dry weather, Rainy weather]
[Illustration: skeleton, flesh]
Saguaros are believed to live to a maximum age of 200 years, usually
succumbing to a necrosis disease transmitted by the larvæ of a small
moth. Grazing cattle trample out the young plants and much of the desert
occupied by Saguaros is being placed under cultivation. Both Saguaro
National Monument and Organ Pipe Cactus National Monument preserve and
protect spectacular stands of these desert behemoths.