CLASSIFICATION OF CROPS 13 



extensive rather than intensive methods are used in the culti- 

 vation of field crops. This rule does not always hold true; 

 the most careful and intensive methods are used in the 

 culture of sugar beets and of some types of tobacco, while 

 fruits and vegetables are sometimes grown in large areas 

 by extensive or field methods. 



5. Classification of Field Crops. It is rather difficult to 

 make a definite classification of field crops, for certain uses 

 may be made of a given crop under one set of conditions 

 and other and very different uses under another. New 

 uses are continually being made of the various crops, so that 

 a classification made now might be materially wrong in a 

 few years. The principal field crops can, however, be 

 included in some one of the following classes: Grain, hay 

 and forage, fiber, tuber, root, sugar plants, and stimulant. 

 This classification is based in part on the portions of the 

 plants which are used, and in part on the uses to which 

 they are put. Medicinal plants and a few others of a mis- 

 cellaneous nature are not grown to any considerable extent 

 and need not be 'considered at length. 



6. Relative Importance. While the complete figures for 

 the Census of 1910 were not available when this book was 

 in preparation, the total area in field and garden crops in 

 the United States was approximately three hundred and 

 fifteen million acres, of which all but about ten million 

 acres were in field crops. These ten million acres were 

 devoted to garden and orchard crops. The total area 



VALUE AREA 



\ALLOTHERS* 



1. Relative areas and values of the important classes of farm crops. 



