GRAZING RESOURCES 185 
settled form of animal husbandry combined with the cultivation 
of food crops. 
Regeneration of Vegetation 
The main objective in pushing back the desert from those 
regions in which aridity is primarily man-induced and limiting 
it to the areas with a true desert climate must again be the re- 
generation of vegetation by natural and artificial means. This 
work must be carried out in regions with ancient forms of land 
use and against a background of increasing human and livestock 
populations which must continue to obtain their livelihood and 
sustenance from the land, while the improvement is going on. If 
the biotic factor could be limited for some 5 or 10 years, it would 
be possible to make full use of the remarkable capacity of de- 
graded types of vegetation to revive, to climb again up the eco- 
logical ladder, and to provide a superior type of vegetation. It 
would then be possible to evolve new controlled systems of land 
use, to provide better sources and types of food, fodder, or fuel, 
without again causing the degeneration of the plant cover back 
to its present condition. There are many examples within the 
area of excellent regeneration of vegetation, even after a few 
years’ protection and sometimes under very low rainfalls. Many 
more areas protected against grazing, browsing, and cutting are 
required to provide the ecologist with his field laboratory in 
which he can obtain the data on botanical composition and suc- 
cession required by the improver of land use practices. 
Many specialists trained in range work in the western United 
States have been posted in the countries of North Africa and the 
Near East in particular. It is natural that they should attempt 
to apply in these new environments the outlook and techniques 
found to be successful in their home states. In particular, they 
have attempted the reseeding of semi-desert rangelands, with or 
without water spreading. With a few exceptions can it be said 
that any success has so far been obtained by the reseeding tech- 
nique. The difficulties which have arisen are associated chiefly 
with the methods adopted and the availability of seeds of adapted 
species. 
