J4 FOR BETTER CROPS 



crops. Furthermare, clover and other legumes are themselves 

 gross feeders on phosphorus, calcium, and potassium. 



It is almost inexplicable that there are people who write and 

 speak at great length and with great energy on the tremendous 

 importance of adding nitrogen to the soil as an element of plant 

 food, but who completely ignore and even deprecate the matter 

 of maintaining in the soil a supply of phosphorus from which 

 we can liberate sufficient amounts for large crops. 



No man can afford to ignore the truth. If there are soils 

 which contain so little phosphorus that we cannot by profitable 

 means liberate sufficient to meet the requirements of large 

 crops, then we should increase the supply; and every man should 

 be sufficiently unprejudiced to ask frankly whether it is more 

 sensible and more profitable positively to increase the total sup- 

 ply of any element of plant food in his soil, or to continue to 

 decrease it by means of crop rotation and the use of decaying 

 organic matter. 



A uniform application of the manure makes all the plant food 

 available 



For the ordinary, strictly live-stock farm from which only 

 hogs and cattle are sold, there is no such thing as reducing the 

 supply of potassium if all liquid and solid manure is carefully 

 saved and returned to the soil, because, as before stated, practi- 

 cally all of the potassium contained in the feed is returned in 

 the manure. In dairy farming a small amount of potassium 

 leaves the farm if milk is sold. 



But even in live-stock farming with all manure saved and 

 returned to the land, we still lose the phosphorus carried away 

 in bones, flesh, and milk, and this fact should not be ignored by 

 the farmer whose crop yields are already limited because of 

 insufficient supplies of phosphorus, even with abundant use of 

 decaying organic matter supplied in clover and farm manure. 

 Indeed, not infrequently we find farmers whose land is so rich in 

 nitrogen and potassium that they grow great crops of straw and 

 stalks, but the phosphorus is so limited that the actual yield of 

 grain produced is only one-half or two-thirds what it should be. 



