424 EXPERIMENT STATION KECORD. 



Cooperative fertilizer and field trials with farm crops, 1910, P. Bolin 

 {K. Landthr. Akad. Handl. och Tidskr., 50 {1911), No. 7, i)p. 538-593). — The 

 experiments were conducted in 23 different counties of Sweden and include 804 

 series in all, viz, fertilizer trials with small grains, green forage crops, potatoes, 

 and meadows, and variety tests with grains, legumes, root crops, and potatoes. 



Fertilizer experiments to determine the phosphoric acid and potash re- 

 quirements of meadow soils, U. Grete (Landw. JaJirb. Schiveis, 25 {1911), 

 Xo. 7, pp. 3S1-Jf69). — The results of 68 experiments in different parts of Switzer- 

 land are reported, showing that in the majority of cases potash and phosphoric 

 acid were beneficial, and that a combination of the two was the most profitable 

 fertilizer to use on meadow soils. 



Comparative experiments with farm manures made with different kinds 

 of litter, S. Rhodin {K. Landthr. Akad. Handl. och Tidskr., 50 {1911), No. 7, 

 pp. 529-537; Meddel. Centralanst. Forsoksv. Jordhniksomrddet, 1911, No. ^//, 

 pp. 11). — These experiments were conducted for 8 years (1903-1910) on a 

 stiff clay soil, plats of which were manured in the spring of 1903 at the rate of 

 35 tons per acre with farm manure made with peat litter, with straw, with 

 even mixtures of these, and with annual applications of artificial fertilizers 

 (285 lbs. Thomas slag, 570 lbs. kainit, and 285 lbs. nitrate of soda). The crops 

 grown were from 1903 to 1907 and in 1909, potatoes; 1908, rutabagas; and 

 1910, oats. 



The total dry matter in the crops harvested from the different plats during 

 this period was as follows : Unmanured, 22,538 lbs. ; manure with peat litter, 

 31,596 lbs. ; with straw litter, 30.967 lbs. ; with peat and straw litter, 30.912 lbs. ; 

 rnd with artificial fertilizers, 29,474 lbs. The manure made with peat litter 

 produced the largest crops and, economically, the best returns for the period 

 considered. The peat litter manure and the mixed peat and straw manure 

 produced the largest yields the first year, while the straw manure did not 

 produce its maximum effects until the third year of the experiment. 



The importance of thorough mechanical treatment of the soil for a large crop 

 production is emphasized in the paper. 



The action and value of stable manure, B. Schulze et ax. (Ar&. Deut. 

 Landw. Gesell., 1911, No. 198, pp. 333). — This is a detailed report of 4 years' 

 field experiments at the Breslau Experiment Station and at other places in 

 Schleswig, a brief account of which has already been noted (E. S. R., 22, p. 716). 

 The experiments were made at eight different places with different kinds of 

 soil and with manures of varying composition. The crops grown included 

 wheat, barley, oats, rye, leguminous plants, rape, flax, potatoes, and sugar beets. 

 In the manures used the nitrogen varied from 0.34 to 0.78 per cent, the phos- 

 phoric acid from 0.13 to 0.39 per cent, and the potash from 0.33 to 0.91 per cent. 



While the results were variable the average amount of the nitrogen of the 

 manure assimilated during the 4 years was 23 per cent. Of this 43 per cent 

 was assimilated during the first year, 27.8 per cent the second year, 16.6 per 

 cent the third year, and 12.6 per cent the fourth year. Of the phosphoric acid 



33.4 per cent was assimilated during the 4 years, and of this 45.1 per cent 

 was assimilated the first year, 27.1 per cent the second year, 14.9 per cent the 

 third year, and 12.9 per cent the fourth year. Of the potash in the manure 



43.5 per cent was assimilated in 4 years, of which 57 per cent was assimilated 

 the first year, 15.5 per cent the second year, 12.7 per cent the third year, and 

 14.8 per cent the fourth year. 



Tlie experiments with manure supplemented with commercial fertilizers gave 

 inconclusive results. 



The denitrifying' action of straw manure, A. G. Doiarenko {Izv. Moskov. 

 Selsk Klwz. Inst. {Ann. Inst. Apron. Moscou), 17 {1911), No. 2, pp. 259-265, pi. 



