598 



CONSERVATION 



first to learn and then to improve on 

 nature's ways. 



In the driest portions of our vast 

 semi-arid region the plants are peculiar. 

 Among the prevailing types, leaves are 

 few and small, or else unfold quickly 

 during the rainy season to wither at 

 once when that short season passes. 

 Such typical desert forms as the cacti 

 never leaf at all ; they are virtual reser- 

 voirs of water, retained by a glazed 

 epidermis, and distributed throughout 

 tissues largely of starch and cellulose 

 abounding throughout in chlorophyll 

 that marvelous substance which enables 

 plants to absorb the energy of light, and 

 by some obscure alchemy to convert it 

 into vital power. In a word, the desert 

 plants are par excellence water-con- 

 serving organisms ; they are nature's 

 devices for making the best and largest 

 use of a scant water supply. By na- 

 ture's methods these plants and their 

 associated animals have been evolved 

 together through the bitter strife for 

 existence against the common enemies 

 of sun and sand. 



The vital processes of the desert or- 

 ganisms are adapted to the retention and 

 utilization of water. The gigantic 

 sahuaro and titanic sahuesa absorb 

 water literally by barrels, fattening 

 enormously during and after each rain ; 

 the nopal and the cholla drink by the 

 bucketful and the bisnaga by the gal- 

 lon, perhaps for the benefit of animals 

 and men during the next dry season. 

 They can hardly take water direct from 

 the air, since their glazed skins are im- 

 pervious, but their rootlets suck liquid 

 from the soil and perhaps draw mois- 

 ture from the air permeating it ; and it 

 is probable that during prolonged rain- 

 less periods they convert a part of their 

 own starch and cellulose into the water 

 required for vital circulation. Simi- 

 larly, the animals of deserts have be- 

 come adapted to life with less water 

 and taken at less frequent intervals 

 than the animals of humid lands ; cer- 

 tain desert mice indeed living for 

 months and years absolutely without 

 drink through digestive decomposition 

 into water and carbonic acid of the 

 starch contained in the seeds on which 



they subsist. Such are among nature's. 

 ways of making the best and largest use 

 of the scanty water supply of arid re- 

 gions. 



In our great Southwest the aborig- 

 ines adapted themselves to the arid con- 

 ditions in a manner nothing less than 

 marvelous to the anthropologist. At a 

 period some three to five centuries be- 

 fore Columbus came (before certain 

 exterminating intertribal wars arose), 

 the region traversed by the Southern 

 Pacific Railway between El Paso and 

 Bakersfield sustained an aboriginal pop- 

 ulation probably three to ten times 

 greater than the present mixed popula- 

 tion sustained in part by imported 

 products. In the magnificently irri- 

 gated Salt River Valley the modern 

 ditches are less extensive and reach a 

 less extended area than the ancient 

 acequias ; while prehistoric represos and 

 temples and houses dot deserts where 

 now no man lives. These ancients were 

 largely agricultural folk ; their descend- 

 ants survive in the Papago Indians of 

 the farther deserts, and in part in the 

 Pueblo peoples of the mesas ; and it can- 

 not be questioned that they were popu- 

 lous throughout this hard region by rea- 

 son of their success in adjusting them- 

 selves to natural conditions and ways 

 of nature, and making the largest and 

 best use of their scanty water supply. 

 The devices retained by their survivors 

 are too many for telling in an hour ; yet 

 they are well worth study, and it be- 

 hooves modern man entering on the 

 conquest of the deserts to first learn and 

 profit by and then improve on their 

 methods. 



A single lesson may be drawn in 

 passing from the customs of desert folk 

 on this continent and others. Just as 

 the plants and animals of our deserts 

 grew up in mutual adaptation and inter- 

 adjustment through common strife for 

 survival against sun and sand, so the 

 native tribesmen entered into the same 

 solidarity; and the plants and animals 

 and men strove together. One effect 

 was to establish a community of feel- 

 ing, centered on water as the chief 

 source of life, the most precious of all 

 commodities ; and those tribes and 



