654 EXPERIMENT STATION RECORD. 



tissues. If there is sufficient water and gas present the cold disorganizes the proto- 

 plasm and nucleus, making germination impossible, but if the protoplasm by drying 

 has reached its maximum concentration and at the same time its minimum activity, 

 the action of low temperatures is not injurious to the seed, which still retain their 

 germinating power. 



FIELD CROPS. 



Cooperative fertilizer experiments, 1904, P. Bolin (K. Landtbr. Akad. Handl. 

 ocJi Tidskr., 44 (1905), Bihang, pp. 117). — Cooperative fertilizer experiments con- 

 ducted under the direction of the Royal Academy of Sweden at a large number of 

 farms in different parts of the country are reported. In all, 280 experiments, com- 

 prising 149 with small grains, 90 with root crops, 36 with meadows, and 5 with win- 

 ter grains, and aggregating 7,100 plats, were made. Earlier work in this line has 

 been previously noted (E. S. R., 15, p. 569). 



Experiments with oats on clay soils showed that the largest and most economical 

 returns were obtained from the use of 178 lbs. of nitrate of soda, 267 lbs. of super- 

 phosphate, and 89 lbs. of 37 per cent potash salt per acre. As in the previous year, 

 nitrate of soda was most effective, every 100 lbs. of this fertilizer giving an average 

 increase of 300 lbs. of grain and a corresponding weight of straw. Superphosphate 

 was of appreciable effect when applied in connection with nitrate of soda, while pot- 

 ash did not generally prove profitable either on clay or sandy soils. General experi- 

 ence teaches that oats are relatively little affected by potash fertilization. On humus 

 and moor soils applications of 89 lbs. of nitrate of soda, alone or with 178 lbs. of 

 superphosphate, per acre gave more satisfactory financial returns, but the highest 

 yields were obtained where the complete application mentioned above was used. 

 Barley on sandy or peaty soils readily responded to the use of potash. 



The results also indicated that on rather heavy soils the nitrate of soda is better 

 applied all at one time before sowing, even when as much as 178 lbs. per acre is used. 

 The smaller application, 89 lbs. per acre, produced especially favorable results when 

 used in this way as compared with its use as a top-dressing. On the lighter soils, 

 however, a top-dressing of 89 lbs. per acre was completely utilized by the crop. The 

 results again indicated that a top-dressing with nitrate of soda has a tendency to 

 increase the yield of straw rather than that of grain as compared with applications 

 of like amounts before sowing. 



The average results for 2 years showed that 267 lbs. of nitrate of soda (half applied 

 as a top-dressing), 267 lbs. of superphosphate, and 356 lbs. of potash salt per acre 

 produced the heaviest yields of potatoes on sandy soils. As observed in previous 

 experiments, the starch content stood in inverse ratio to the yield, but the largest 

 total yield of starch per acre was obtained on the fertilized plats. The results indi- 

 cated that in general potatoes grown for factory purposes are more profitable when a 

 medium application of fertilizers is used than when heavy applications are given for 

 the production of a maximum crop. 



Mangels grown on humus soils responded most readily to phosphatic fertilizers. 

 The heaviest yields were obtained from the use of 89 lbs. of nitrate of soda, 356 lbs. 

 of superphosphate, and 267 lbs. of potash salt per acre. 



On meadows where grasses predominated, especially on soils low in nitrogen, the 

 most economical results were generally obtained by applications of nitrate of soda, 

 while in fields where the stand consisted largely of clover and the soil was high 

 in organic compounds, phosphates and potash produced the best results. 



Comparisons were made of ammonium sulphate and nitrate of soda in a series of 

 14 experiments with roots and small grains. The heavy applications consisted of 

 267 lbs. of nitrate of soda per acre for roots and 178 lbs. for grain, and the light 

 applications of 178 lbs. and 100 lbs. per acre for roots and grains, respectively. The 



