Causes of Clover Failure 703 



per cent phosphoric acid, althoui^'h I have purchased that which 

 ran as high as 8 per cent potash. A half-ton of 5 per cent ash 

 applied to an acre would contain only 50 pounds of potash, or as 

 much as is contained in 100 pounds of muriate. 



Phosphoric acid is also a very necessary factor. Usually this 

 can be most economically supplied in acid phosphate, in which 

 form it is quickly available — most important for the young 

 clover. 



While clover is a nitrogen gatherer, it cannot do this until it 

 has attained size and considerable leaf growth. For this reason 

 nitrogenous manures show good effects, as has been stated. If 

 there is an abundance of nitrogen in the soil, the evidence is 

 that the plant will take little from the air ; therefore, it is unwise 

 to give the clover an excess of this element when it is well grown. 

 ISTevertheless, it is absolutely necessary for its best growth that it 

 should have enough to give it a start. I have used from 75 to 100 

 pounds of nitrate of soda per acre w'ith marked results. Being 

 quickly soluble in cold weather, this is the most economical form 

 in which to buy nitrogen. 



vegetable matter 



This is closely allied to the question of fertility, for the amount 

 of nitrogen in any soil is always commensurate with the quantity 

 of vegetable matter it contains. 



Decaying vegetable matter produces an acid that liberates 

 lo^ked-up mineral matter in the soil, of which we are told there 

 is an abundant supj^ly. It also acts as a sponge to retain moisture. 

 As I am writing, there has been a period of about two weeks with- 

 out rain. A field of corn just west of the highway is curling for 

 lack of moisture, the soil being deficient in vegetable matter. In 

 two fields across the road belonging to different men there is corn 

 with a much more abundant growth, making a greater demand 

 for moisture, but there is not a sign of curl. There, the soil is 

 full of humus. 



Again, vegetable matter, like manure, is a necessary breeding 

 place for soil bacteria. There are usually clover bacteria in land 

 where clover has been previously grown ; but, unless there is 

 decaying vegetable matter present in fair amount, these" cannot 



