No. 4.] GERMAN EXPERIMENT STATIONS. 399 



(b) The legumes will utilize the soil-nitrorien hi })refer- 

 ence to the air-nitrogen, providing they have the oppor- 

 tunity. 



(c) Generally speaking, it is not advisable to ap[)ly any 

 nitroijen to aid in the o'rowth of leiz'uniinous erons. There 

 are, however, exceptions, as, for example, on sandy soils- 

 very poor in nitrogen. In such a case the crop at a ver}' 

 early sta<>"e in its o-vowth beiiins to manifest its hunsfer 

 for nitrogen. If at that period 80 to 40 pounds of soda 

 nitrate are applied per acre, this nitrogen-hunger will be 

 relieved, and the plant becomes stronger and better able to 

 exist till the bacteria co-operate with it in supplying the 

 nitrogen needed. 



{(I) The grains in the following order, viz., barle3% wdieat, 

 rye and oats, have the greatest need of soluble nitrogen, 

 such as nitrate of soda and sulphate of ammonia, because 

 of their short growing period ; while roots, late ])otatoes 

 and grasses, having a longer ])(n"iod of growth, can use 

 the slower acting forms of nitrogen, such as stable manure, 

 tankage, bone nitrogen, etc., to better advantage. 



(e) The following iigures, which must not be too literally 

 construed, may prove interesting to some : — 



To produce — 



100 pounds oats with straw requires 24 pounds Chili saltpetre. 



100 pounds wheat with straw re(iuires 32 pounds Chili saltpetre. 



100 pounds rye with straw recjuires 32 pounds Chili saltpetre. 



100 i^ounds barley with straw requires 25 pounds Chili saltpetre. 

 1,000 pounds potatoes with tops recjuires 28 pounds Cliiii saltpetre. 

 1,000 pounds sugar beets with tojis requires IG pounds Chili saltpetre. 

 1,000 pounds fodder beets with tops requires 19 pounds Chili saltpetre. 



From the above figures it can l)e calculated that 100 

 pounds of Chili saltpetre will produce, in round numbers : — 



400 jiounds oats with straw. 



300 jDounds wheat with straw. 



300 pounds rye with straw. 



400 pounds barley Avith straw. 

 3,600 i^ounds potatoes with tojjs. 

 6,400 pounds sugar beets with tops. 

 5,500 pounds fodder beets with tops. 



