1902.] PUBLIC DOCUMENT — Xo. 33. 21 



plots. The results previous to this year were thus sum- 

 marized in the last aimual report : — 



Taking into account the periods wlien chemical fertilizers only 

 Avere used, and the crops (spinach, lettuce, onions, table beets, 

 garden peas and carl}' cabbages) whose peritxl of growth is the 

 comparatively early part of the season, we find tlie relative elli- 

 cieucy of the different materials used as the source of nitrogen : — 



Per Cent. 



Nitrate of soda, 100.0 



Dried blood, 86.6 



Sulfate of ammonia 83.6 



For the same periods, and taking into account those crops 

 (tomatoes, garden beans and sweet corn) making much of their 

 growth after hot weather fairly sets in, we find the relative stand- 

 ing as follows : — 



Per Cent. 



Nitrate of soda, 100.0 



Dried blood, 97.8 



Sulfate of ammonia, 103.5 



For the period since manure has been applied, and taking into 

 account the early crops only (spinach, lettuce, table beets, onions, 

 garden peas and potatoes) , the relative standing is : — 



Per Cent. 



Nitrate of soda, 100.0 



Dried blood, 88.8 



Sulfate of ammonia, . .61.7 



For the same period, taking into account the aggregate yield of 

 all the late crops (tomatoes, cabbages, turnips, squashes and 

 celery), the relative standing is : — 



Per Cent. 



Nitrate of soda, 100.0 



Dried blood, 97.8 



Sulfate of ammonia, 91.9 



The crops for the past year have been onions, lettuce, 

 table beets, late cabbages, garden peas, celery and English 

 turnips (both as second crops) and strawberries. The 

 average rates of yiekl per plot for each of the nitrogen fer- 

 tilizers is shown in the following table : — 



