380 STATE HORTICULTURAL SOCIETY. 



It is, therefore, not a matter of indifference in what form a phos- 

 phatic fertilizer is bought, and careful and frequent analyses of the 

 brands offered for sale are necessary to protect the buyer. Our 

 present state inspection law is defective and does not secure it ; no 

 general standard brands like those of the Strassfurt potash salts or the 

 nitrate are accessible to the retail trade, hence the product of the un- 

 scrupulous and fraudulent concern stands upon an equality with that 

 of the reputable and honest house — a condition which is unjust to the 

 latter and confusing to the farmer who wishes to buy. No tabulation 

 as to cost and amount per acre of the phosphoric acid in a crop is, for 

 that reason, attempted. 



Nitrogen — The term " available," so often used in regard to plant- 

 food, implies solubility in water, since the roots of the plants can suck 

 up and absorb nothing but what is soluble. This applies to potash and 

 phosphoric acid, whose insoluble compounds in the soil are nearly 

 valueless, and is still further limited in the case of nitrogen by addi- 

 tional conditions. Thus the vast amount of elementary nitrogen stored 

 up in our atmosphere is completely unavailable excepting in those 

 special cases to be described later; likewise does the available nitro- 

 gen in the soil suffer gradual but continued loss through surface wash- 

 ing or under-drainage, by which this most desirable and costliest of all 

 the plant-food demands more careful and more intelligent attention 

 than the rest. 



We know there are virtually but two classes of nitrogen com- 

 pounds, which, on account of their solubility and the experimental 

 proof furnished therefor, can be taken up and assimilated by the plants ; 

 these are ammonia salts and salts of nitric acid ; we also know by prac- 

 tical trials with our cultivated crops that the latter are more effective 

 than the former, and are in all probability that form of nitrogen which 

 the plant can most readily utilize ; all others can serve the needs of 

 the plants only after conversion into nitrate, which takes time and 

 renders their use much less effective. While therefore not excluding 

 salts of ammonia, such as sulphate or muriate, there is no doubt but 

 that nitrates are preferable and cheaper, and are in reality the rational 

 source of nitrogen supply for our crops, with which we compare all 

 others as to price and efficiency ; these others are of two main sources ; 

 animal or ground fish, bone, scraps and the multifarious refuse of our 

 slaughter and packing-houses; and vegetable, as f. e. cotton-seed meal 

 and similar articles, whose nitrogen, to repeat it, is not immediately avail- 

 able to plants, but must first pass through a series of changes within 

 the soil into compounds of ammonia, which the plant may take up, but 

 which it finds some difficulty in easily digesting. These changes pre- 



