Midwinter botanizing in southern Arizona 
Epwin B. BARTRAM 
As a large part of the literature relating to the desert flora 
of Southern Arizona is not readily accessible to any but pro- 
fessional botanists the following brief survey of the recognizable 
winter plants in the region tributary to Tucson may prove 
interesting and helpful to those fortunate enough to make the 
ce mage a of this fascinating country in the early months 
of the y 
From a ee point of view the area is obviously more 
closely related to the Mexican state of Sonora than it is to any 
of our possessions so that many of its most characteristic plants 
are not represented at all in Wooton and Standley’s invaluable 
Flora of New Mexico. 
The preparation of specimens in this dry sunny climate is a 
simple operation; the surrounding mountains, or at least their 
foothills, are easy of access; and, as the representation of Arizona 
plants in most of our larger eastern herbaria is quite meagre, 
the ambitious collector finds an almost unlimited field in which 
to work. A surprising variety of flowers is evident even at this 
season and many plants whose period of bloom is past are re- 
cognizable by some peristent vestige of fruit or flowers. 
Apart from such unique and unfamiliar plants as the sahuaro, 
chollas, candle bush, prickly pears and palo-verde, which claim 
the undivided attention of the newcomer until the novelty and 
charm of the first impressions are to a certain extent dulled by 
familiarity, the most striking feature of the desert vegetation is 
the isolation of various clearly defined plant communities. It is 
all desert, to be sure, but the wide gravel plains over which Covtllea 
glutinosa is dominant and the barren spurs and talus slopes, 
sun baked, arid and almost devoid of plant life, excepting the 
hardiest drought-resisting species that have become inured to 
this environment, seem to resolve themselves readily into a 
series of barriers that from necessity restrict the distribution of 
many species to quite definitely circumscribed limits. 
Distances in Arizona are proverbially deceptive, but we were 
hardly prepared to learn that the lower slopes of the Santa 
Catalina Mountains, which looked so enticingly near, were at 
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