types are recognized and have been measured in many local situations, 
highly reliable data are lacking as to the magnitude and distribu- 
tion of the aggregate losses on a national basis. 
Even if such data were available in physical terms, no satisfac- 
tory method has yet been devised for the precise evaluation of the 
economic effects of such losses to the farmer and to the consuming 
public. Under the conditions of inelastic demand which so frequent- 
ly characterize the agricultural "economy of scarcity," the full 
social value of agricultural production, or of any diminution of 
such production, cannot adequately be expressed by the price tag 
of the market value. With full regard for these limitations, an ate 
tempt has been made to aggregate loss estimates in terms of physi- 
cal losses and their economic evaluation. The nature and extent 
of losses dus to various causes are then described. 
Physical Losses 
Estimates of the physical soil loss from cropland for the base 
period run as high as billion tons per year. One-third to one- 
fourth of this amount ultimately enters the major stream systen, 
with resultant damages from flooding, sedimentation, etc. About 
35 million acres of land originally suitable for cultivation have 
been rendered unfit even for temporary cultivation by the various 
types of soil deterioration, principally soil erosion. For the 
base period the annual rate of such cropland loss is estimated at 
500,000 acres per year. In addition, 50 to 100 million acres of 
land, once cultivated but not originally entirely suitable for 
long-time cultivation, have been so severely affected that they 
are no longer in cultivation. 
On land that has remained in cultivation, soil deterioration has 
given rise to losses of a much more serious nature, in terms of 
decreased yield and increased costs. A survey by the Soil Conser- 
vation Service in 1948 indicated the following conditions on the 
450 million acres of cropland at the current rate of soil deterioration: 
sNumber of years in which land 
3 : would be degraded one capability 
Degree of : Million : class 1/ if no remedial measures 
deterioration g acres : were taken 
Critical 114 10-15 
Serious 120 15-30 
Slight to none 216 30 plus 
1/ Based upon the SCS land-capability classification, which is a 
systematic arrangement of different kinds of land according to 
properties that determine their capability to produce perhanently. 
- 162 - 
