ROTATION OF CROPS 205 



the impossible; it is running the risk of reaping 

 only a very mediocre harvest or even none at all. 

 Therefore it is the rule not to sow wheat twice in 

 succession in the same field. And what is true of 

 wheat is true also of all other crops. Where a 

 plant has prospered one year, the same plant will 

 not do well the second year, because the ingredients 

 required by this plant are more or less exhausted. 

 It is foolish to invite guests to a table that is stripped 

 bare. 



"If the table were spread again, if more fertilizer 

 were added to the soil, that would be quite a differ- 

 ent matter, and wheat would grow as well as it did 

 the first time. But such a procedure would be bad 

 management, for the very utmost should be made 

 of one meal. Before further expenditure in the way 

 of fertilizer let us exhaust the virtue of the fertilizer 

 already applied. Azor dined well on what Jacques 

 discarded; the hens were well fed with what Azor 

 and the cat left. Let us take an example from this 

 succession of eaters who utilize each in his own way 

 the remnants worthless to the others. The wheat 

 has exhausted, or nearly exhausted, all that is suit- 

 able for wheat; but just as Jacques the ox-driver 

 left the bone, it has left in the soil a good many 

 ingredients that make excellent food for other crops. 

 In order, therefore, to utilize to the last ounce the 

 first spreading of fertilizer, we must invite to the 

 repast a guest of different tastes. This guest may 

 be, for example, the potato. In soil that would have 

 furnished but starvation diet for wheat the potato 



