The Role of Science 
in Man’s Struggle on Arid Lands 
CHARLES E. KELLOGG 
Soil Conservation Service, United States Depart- 
ment of Agriculture, Washington, D. C. 
History tells us a great deal about the relationship of man to 
his land in arid regions. Broadly it tells us that man can live on 
such lands, but to live well and to prosper he must make full use 
of science and technology for the combined use of all the resources. 
First, ‘‘arid lands” as used in this paper must be defined. In- 
cluded specifically are those regions in which the normal soils, 
although perhaps productive of grass and browse, are usually too 
low in moisture for the dependable production of cultivated 
plants without irrigation. Many of the characteristics of arid 
lands thus defined are found in slightly less dry regions where the 
soils will support crops of cereal grains in alternate years without 
irrigation if special practices are followed to conserve moisture. 
The boundary between the sown and the unsown is wide and 
shifting. Under extreme pressure for food, cereal growing com- 
monly pushes out onto arid soils too dry for sustained production. 
The Balance We Seek 
The central problem of land use and human living in arid re- 
gions, as elsewhere, is to maintain a reasonable fit between society 
and resources. 
Among very primitive people, comparatively isolated and hav- 
ing few tools, perhaps one may talk about a “natural balance”’ 
of some sort. But such a concept has limited relevance today. 
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