936 EXPERIMENT STATION RECORD. 



Utilization by plants of the phosphoric acid dissolved in soil 

 water, T. Schloesin< i ( ( 'ompt. Rend. Acad. Sci. Paris, l 2? ( 1898), Xo. 21, 

 pp. 820-822; abs. in Rev. Sci. [Paris], 4. ser., 10 (189* ), No. 23, p. 725).— 

 Sterile sandy soils especially deficient in phosphoric acid were watered 

 with nutritive solutions containing - varying amounts of phosphoric acid 

 and planted to various crops. On the soils receiving no phosphoric 

 acid the plants made little or no growth. On those receiving phos- 

 phoric acid in proportions similar to those found in ordinary soils the 

 plants grew well. With solutions containing 2 mg. of phosphoric acid 

 per liter excellent crops of maize were obtained, and with solutions con- 

 taining from 0.5 to 1 mg. of this substance per liter the yield of wheat 

 was from 13.35 to 24.03 bu. per acre. 



Trial of phosphates, 0. O. Flagg and J. A. Tillinghast (Rhode 

 Island Sta. Rpt. 1897, pp. 394-408, pis. 2, (Ignis. 4). — The plan of these 

 experiments and the results heretofore obtained have been previously 

 published (E. S. R., 9, p. 938). A hay crop was grown in connection 

 with these experiments, and the yields in 18 ,6 and 1897 are reported in 

 tables and the results described. The different materials used to supply 

 phosphoric acid were dissolved boneblack, dissolved bone, dissolved 

 phosphate rock, fine ground bone, slag meal, floats, raw aluminum phos- 

 phate, ignited aluminum phosphate, and double superphosphate. These 

 substances were applied on two series of plats, one of which was 

 unlimed, while the other had received an application of 1 ton of air- 

 slaked lime per acre in 1894. 



"The 3 insoluble phosphates, fine ground bone, slag meal, and floats, thus far main- 

 tain the lead in pounds of hay produced, slag meal holding the first place in the 

 unlimed series. The aluminum phosphates thus far appear to be quite inferior 

 forms of phosphoric acid when used upon an acid soil without an application of 

 lime; and when iu the raw form, even in connection with lime, produced a smaller 

 crop than the plat which received no phosphoric acid. The ignited form, used in 

 connection with lime, produced, in 1897, the second largest yield, but occupies sixth 

 place in the total production for 2 years. The last one-third ration has yet to be 

 applied as an annual top-dressing to the plats receiving the soluble phosphates 

 before all will be on the same basis, but the lead now held by 3 forms of insoluble 

 phosphate will doubtless give them the advantage even then." 



In the 2 seasons the lime plats yielded G,G34.42 lbs. of hay per acre 

 more than the unlimed plats. "If ... we charge the entire cost of 

 the lime at $8 per ton to these 2 hay crops and calculate the value 

 of the increase in the hay crop at $14 per ton, we have a profit of $38.44 

 per acre due to the use of lime in connection with fertilizers on an acid 

 soil." Redtop (Agrostis vulgaris) formed the bulk of the hay crop on 

 the unlimed plats and timothy (Phleum pratense) on the limed plats. 

 The use of air-slaked lime favored the growth of the timothy. " When 

 soils are acid, timothy quickly disappears from the grass field and red- 

 top or dent or, perhaps, sorrel takes its place." 



Tests of nitrogenous fertilizers on hoed plants, C. Dusserre 

 (Chron. Agr. Vaud, 11 (1898), Xo. 23, pp. 668-672).— An account is given 

 of 2 experiments with varying amounts (200 to 500 kg. per hectare) of 



