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Fig. 22. Home of the Palo Verde, Laboratory Hill, Tucson, Arizona. 

 (Courtesy of the Popular Science Monthl}'.) 



PALO VERDE 



THE EVERGREEN TREE OF THE 

 DESERT. 



Bv Professor Francis E. Llovd. 



To the artist and botanist alike the play of colors in the desert 

 is most fascinating, and not a small part in the change of colora- 

 tion from month to month is taken by the flowers, which develop 

 in great numbers and with remarkable rapidity after the sea- 

 sonal rains, which occur in early spring and in the late summer. 

 The fact that there are two rainy seasons in onr southwestern 

 deserts results in what we may very well describe as two springs,^ 

 instead of spring and autumn. It is noteworthy, however, that 

 the plants which develop into flower and fruitage after the sum- 

 mer rains are not in general the same as those which develop 

 during the spring. 



It is my purpose in this article to speak particularly of a plant 

 which, during the latter part of April and early May, supplies 

 the dominant note of coloration in such regions as the desert 

 about Tucson, Arizona. I refer to the palo verde. of which there 

 are three species, known as Parkinsoiila niicrophylla, P. acidcata 



