638 EXPERIMENT STATION RECORD. 



amounting to about 5 per cent of the manure reduced the loss of nitrogen to 

 some extent, but owing to the large quantities required and the sulphur com- 

 pounds formed as the result of reduction processes and which are injurious to 

 plant growth, gypsum is not recommended as a preservative for barnyard 

 manure. 



The most complete preservation of barnyard manure was secured by separa- 

 ting the liquid substance and preserving it by itself, while the solid manure was 

 allowed to rot with water. This method is not opposed to the old rule that 

 manure should be kept moist and compact, but rather accords with it as in 

 both cases losses are prevented by excluding the air from the liquid substance. 

 Furthermore, when liquid manure is stored separately the organisms which 

 act injuriously are not at all, or but slightly, active on account of the lack of 

 carbon which in mixed manure is so abundantly suiiplied by the solid excrement 

 and the litter. 



The nitrogen derived from green manuring was well taken up by beets and 

 oats, while potatoes on the better soils were very irregular in using this supply 

 of plant food. It is stated that as a result of the cultivation of the potato 

 crop, which is similar to fallowing the land, so much nitrogen is made available 

 on fairly fertile soils that this covers the requirements of the crop and that con- 

 sequently little use is made of the nitrogen which may have been supplied by 

 green manuring. The certainty with which Inirnyard manure proves ad- 

 vantageous to the crop is attributed largely to the potash content of the 

 manure. A mixture of peas and beans grown after a crop of early spring barley 

 and winter barley, and rye sown with clover, especially yellow clover {TrifoUum 

 agrarium), gave the best results in green manuring. 



The tests with commercial fertilizers showed that nitrate of soda was best 

 adapted to most crops, although potatoes used ammonia with equally good re- 

 sults. Norwegian calcium nitrate was equally effective with nitrate of soda, 

 while lime nitrogen showed about 80 per cent of the effectiveness of nitrate of 

 soda. These different substances, however, were not utilized with equal readi- 

 ness by all crops, potatoes and cereals making better use of them than beets. 

 It was also found most profitable in the culture of winter cereals to apply all of 

 the nitrogen in the form of nitrate of soda in the spring. 



A rotation consisting of fallow, rape, wheat, rye, oats, and oats showed a def- 

 icit of 225.69 marks per hectare (about $22 per acre) at the end of the 6 

 years as compared with a rotation in which a crop of peas was substituted for 

 the fallow. In a second rotation experiment fallow, wheat, beets, barley, and 

 oats as a crop succession gave at the end of the 5 years a return of 225.62 marks 

 per hectare less than a rotation including peas in place of the fallow. 



The inoculation of horse I)eans. peas, and alfalfa with pure cultures remained 

 without effect, while the inoculation of serradella, a crop not theretofore grown 

 by the station, was of much benefit to the crop. Seed treated with Issleib nutri- 

 ent solution gave no better results than seed soaked in water. 



In the variety tests with wheat the best yields were obtained from Jaensch 

 White, Strube squarehead, and Rimpau squarehead wheats. The successive 

 culture of these varieties for 3 years gave no indication of degeneration. Pro- 

 tein and gluten content varied very much in the different years, the foreign 

 and spring wheat varieties ranking first in this respect. The content of the 

 nitrogenous nongluteuous substances in the grain of the same year was almost 

 exactly the same, so that differences in protein content were due to differences 

 in the gluten content. 



Baking quality was found less dependent upon the variety than upon season, 

 time of harvesting, lodging, etc. It was also shown that a high gluten content 



