The Function of Manures and Fertilizers 31 



as crops in the same light as the others, and were seldom 

 the source of direct income. At the present time, vege- 

 tables and fruits are regarded as necessities in every home, 

 and their use is not confined to the season in which they 

 can be provided in the immediate vicinity of the cities 

 or towns where they are used ; they are drawn from points 

 far distant, and the demand is such as to require the use 

 of wide areas in order to supply the needs. The growing 

 of market-garden crops and fruits is now the basis of 

 specific agricultural industries which have assumed large 

 proportions. 



Much progress has been made, too, in the develop- 

 ment of methods of practice in these lines of farming, 

 and the experience gathered has shown that even our 

 most fertile soils in their natural conditions contain 

 too little active food to insure maximum yields of crops 

 of the best quality; in these lines of farming, too, earli- 

 ness and edible quality of products, which are influenced 

 by the food supply, are important factors in determining 

 the profits to be derived. The areas now necessarily 

 devoted to these crops are so great that soils of a high 

 natural fertility, even if natural fertility alone could be 

 depended upon, are too limited to meet the demand and 

 enable a profit, especially in the vicinity of good markets ; 

 in other respects a good location, because permitting of 

 cheap distribution, is an important factor. 



Farm manures are inadequate. 



Farm manures might meet the needs for the staple 

 crops, as they are well adapted in many respects for 

 the purpose, but, under present systems of manage- 

 ment, the amount is not sufficient to meet the annual 

 losses from the sale of crops, much less to provide an 



