154 BOARD OF AGRICULTURE. [Pub. Doc. 



8. Upon acid or light sandy and gravelly soils, sulfate 

 of ammonia is liable not only to give inferior results, but to 

 act as a poison unless slacked lime or wood ashes is first 

 applied to the soil. 



9. Dried blood is generally considered to be the most 

 effective form of organic nitrogen obtainable. In its pur- 

 chase, however, the high grade, containing from 12 to 13 

 per cent of nitrogen, is less likely to be found adulterated 

 than the lower grades. The assimilability of the nitrogen 

 of blood is eventually, under the most favorable soil condi- 

 tions, not far l^ehind that of sulfate of ammonia, though, 

 owing to the necessity of its first being changed to ammonia, 

 it does not usually act so quickly. 



10. The nitrogen of cotton-seed meal, linseed meal, 

 castor pomace, fish, tankage and horn meal is not so quick 

 in its action as that of blood, for which reason it is not so 

 well adapted to greenhouse work. For tobacco, or whatever 

 crops enjoy a long period of growth and in seeding land to 

 grass, these materials are particularly applicable, provided 

 they can be had at a reasonable price. Unless the price is 

 very low, top-dressing with nitrate of soda just as the grass 

 is starting will prove much more economical. 



11. Organic nitrogen is particularly applicable upon very 

 light soils, where loss of nitrogen by leaching is to be feared, 

 for the reason that it is continually l)ecoming assimilable, 

 and is always present to some extent to meet the demands 

 of plants. 



12. A given amount of organic nitrogen, if quite readily 

 assimilable, as, for example, in blood, may, under certain 

 circumstances, produce a greater ^deld than the same amount 

 of nitrogen in the form of ammonium salts or nitrates, pro- 

 vided the latter materials are all applied in large quantities 

 at once, when the plants are very young or before growth 

 has commenced. The reason for this is that excessive 

 amounts of those salts may act injuriously upon young and 

 tender plants. When applied properly and in limited 

 amounts, a given amount of nitrogen as nitrate of soda or 

 as sulfate of ammonia may, as already stated, be expected 

 to give a considerably greater yield than as organic matter. 



