of Soda alone insures this. With other forms of Nitrogen Food for 



plant food, rains or cool weather interfere 



with the regular supply of Nitrate, by H . ow a11 37 



checking the action of the organisms which Nitrogen is, 



cause the Nitration of crude substances. |. Necessity, 



Top-dressings are also used on very rolling ' a 



lands, in which case the hill tops show Slowness. 



lighter-colored foliage in prolonged periods ocess. 



of dry weather, and light applications of Nitrate of Soda 



are found to be profitable. 



On heavy clay soils, spring working is impracticable, as 

 it results in puddling the top soil. In this case fertilizers can- 

 not be worked into the soil even for spring planting, and 

 Nitrate of Soda is used in the form of a top-dressing spread 

 broadcast. 



In top-dressing soils, it is very import- 

 ant to secure an even application over the " ow to P- 

 whole area. As the ordinary application ^ re ss. 

 per acre is about 100 pounds, it is difficult to get an even 

 distribution unless the bulk of the material is increased. The 

 best method of doing this is to crush the Nitrate of Soda 

 thoroughly and mix carefully with about its own weight of 

 fine dry loam. This mixture should only be made immedi- 

 ately before using, though the Nitrate may be crushed at 

 any time if mixed at once with an equal bulk of fine, clean 

 sand. Where top-dressings are made with a machine, it is 

 necessary that the mixture be dry. 



Top-Dressing Experiments. 



The official Agricultural Experiment 

 Stations have made many experiments to Results or 

 determine the value of top-dressings of Nitrate on 

 Nitrate of Soda, particularly the New Mone V Cr P s - 

 Jersey Station. The work of this Station demonstrated the 

 profit value of Nitrate top-dressing on various fruits and 

 vegetables. The Rhode Island Experiment Station (see Bul- 

 letin 71) made a top-dressing test on grass land and the 

 results also indicated a profitable use of this chemical fer- 

 tilizer. 



The experiment was made on three plots, all of which 

 were treated with ample quantities of Phosphoric Acid and 



;.!4248T> 



