1 62 PRINCIPLES OF RURAL ECONOMICS 



might reasonably be expected to yield under thorough cultivation. 

 Another author might reasonably ascribe different yields and get 

 different results, though the present writer believes that his own 

 estimates are reasonable, and he is certain that the yields which 

 he has ascribed to the different crops are attainable. 



In addition to the food-producing power of the different crops 

 in our country, as shown by the table on page 161, that of an 

 acre of tropical land in bananas, dates, and other tropical fruits 

 is very great. When this is considered in connection with the 

 fact that these fruits are grown in countries where land is still 

 abundant and cheap, it is apparent that the food question is 

 easily solved for a long time to come for those countries which 

 are willing to accept the banana, the date, etc., as articles of 

 diet, and which are able to produce something to give in ex- 

 change for these. Given these conditions, the food problem is 

 merely one of transportation. 



Effect on standard of living. The objection to such a change in 

 habits of consumption as will require more of the heavy-yielding 

 and less of the light-yielding crops is that it may be carried to 

 the point of lowering the standard of living. Such is likely 

 to be the case where a cheap diet is substituted for an expen- 

 sive one without any increase in variety. The substitution of the 

 potato for bread is one thing ; the addition of the potato as a 

 part of a diet which had previously consisted mainly of bread is 

 quite another thing. The former lowers the standard of living, 

 while the latter, by introducing greater variety, tends to improve 

 it, and at the same time to reduce its cost. 



It is, however, unfortunate for a people to become depend- 

 ent upon a single heavy-yielding crop, especially if that crop 

 be, like the potato and certain edible roots consumed in such 

 large quantities in Japan, of rather low nutritive value per 

 pound. The yield per acre being so enormously large, the food 

 value per acre may be somewhat large also in spite of the low 



