MANUEIAL VALUE OP FEEDING STUFFS 277 



value, as surely as would the application to the same land of mixed com- 

 mercial fertilizers worth this amount. 



436. Selling fertility. The table in the preceding article further 

 shows that those who sell such crops as hay, corn, and wheat part with 

 far more fertility for a given sum of money than do those who sell 

 animals or their products. The farmer who sells 1,000 Ibs. of clover hay, 

 worth $6 to $10, parts with about as much fertility as if he had sold 

 1,000 Ibs. of fat steer or pig, worth $70 to $100, or more. Based on 

 the selling price, milk carries considerable fertility from the farm, and 

 butter practically none. Farm crops may be regarded as raw products, 

 while farm animals, milk, wool, butter, etc., represent manufactured 

 products. A large amount of raw material in the form of grass, hay, 

 corn, etc., is put into animals, and the heavy waste or by-product 

 resulting, in the form of manure, when carried back to the fields con- 

 serves most of the fertility. The farmer who feeds his crops to live 

 stock is a manufacturer as well as a producer, with two possible profits 

 instead of one, while his farm loses little of its fertility. The farmer 

 who grows and sells grain, hay, and straw is selling a large amount of 

 fertility, the need of which will surely be apparent as time goes on and 

 his fields give smaller and smaller returns. Such a farmer is slowly 

 but surely mining phosphorus and potash from his soil, which can be 

 replaced only by some purchased material. 



Virgin soils as a rule contain great quantities of available fertility, 

 and the pioneer farmers in America, drawing upon Nature's store, have 

 given little consideration to how their crops are fed and have not 

 realized that they are steadily and often wastefully drawing on the 

 store of fertility which represents their principal capital. The western 

 farmer, when marketing corn or wheat, or the southern planter, when 

 selling seed cotton, considers he is selling labor and rent of land. 

 Rarely does he realize that he is also selling fertility, to replace which 

 would cost a considerable part of all the crop brings. Rather than to 

 reckon the value of his crop at the market price, he should recognize 

 that its true value when sold from the farm is really the market price 

 minus the value of the fertility which the crop removes from the soil. 



437. Buying fertility in purchased feeds. Even in live stock farming 

 where little or no grain or roughage is sold and when proper care is taken 

 of the manure, not all of the fertility removed in the crops is returned 

 in the manure. The growth of legumes will aid in maintaining the 

 nitrogen supply in the soil, but under actual conditions on most farms, 

 supplying additional nitrogen in manure or fertilizer will increase crop 

 yields. Sooner or later in practically all cases it is necessary to replace 

 the small but steady loss of phosphoric acid and potash, even when most 

 of the crops are fed to stock and the manure is handled properly. There- 

 fore, in purchasing feeding stuffs, one should always consider not only 

 their feeding value but also their worth as fertilizers. By a wise selection 

 of purchased concentrates the live stock farmer can build up the fertility 



