The Desert Flora of Phoenix, Arizona 
By RicHarpD E. KUNZE 
The Sonoran flora of the Salt River Valley of Arizona, between 
Phoenix and Tempe, during December, January and February of 
each year presents such a strong contrast to that of the north, that 
a description of it as seen after the autumn or winter rains may 
not be out of place. This valley has an altitude of 1,100 feet 
above the sea, is about sixty miles long and has a width of nearly 
twenty miles. It once was an inland sea, and the red sand buttes, 
largely composed of conglomerate rock, plainly show the effect 
of erosion on every side. From east to west this valley is traversed 
by the Salt and Gila rivers. To the north it is bounded by the 
Phoenix mountains, and to the south by the Maricopa mountains, 
running east and west, and the Estrella mountains, westward. In 
various places sandstone buttes jut out from the mountain into the 
valley. 
At the beginning of December, when the deciduous shrubs 
and trees of the bottoms defoliate, those of the deserts adjoining 
put ona verdure which lasts until the succeeding spring. The 
cactus desert proper extends only from two to four miles on every 
side of these mountains, changing then into the sagebrush desert, 
which in turn is bounded by the bottom lands of the rivers. The 
striking feature of the Sonoran flora is the giant cereus or “saguara”’ 
of the Mexicans, Cereus giganteus, reaching here a height of forty 
feet and over. In April and May this Cereus giganteus has large 
white flowers, which appear at the end of candelabrum-like branches, 
and arranged in crescentic rows encircling the stem, to the number 
of fifty and seventy-five on a single stem. In July the scarlet 
fruit appear, which are luscious and are gathered by Indians and 
Mexicans to be made into jelly and sweetmeats, or eaten raw. A 
wine is obtained from it by fermentation. 
Echinocactus Wislizeni or fishhook cactus, is here found in the 
crevices of the rock. It more largely affects the mountain sides 
or rocky “arroyos,”’ which carry the waters to the bottoms. A 
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