946 EXPERIMENT STATION RECORD. 



confined, however, to tests with the wire-basket method. The results obtained with 

 the heavy clay Strongsville soil are thus summarized: 



" (1) The soil has been greatly improved by placing it in good physical condition 

 such as is obtained in potting. 



" (2) The soil is naturally fertile so far as plant food is concerned, as shown not 

 only by the basket cultures but as indicated by the result of the chemical analyses 

 reported in Bulletin 150 of the Ohio Agricultural Experiment Station. 



' (3) The effect of replanting the untreated soil in pots with wheat immediately 

 after a crop of wheat has been growm in the same is to reduce the growth of plants 

 approximately 50 per cent. 



" (4) Lime appears to have some beneficial effect in the baskets. Heavier appli- 

 cations than the results in the baskets would seem to indicate have been found 

 practicable in the field, probably owing to the physical effect which this substance 

 has upon the soil. 



" (5) No appreciable difference is detected between the results obtained with 

 ground quicklime and hydrated lime. 



,l (6) Little if any beneficial effect has been showm from the application of mineral 

 fertilizer salt to this soil after it has been placed in good physical condition, although 

 an application of these salts, especially acid phosphate, gives a decided increase 

 when the soil is in the condition found in the field. 



" (7) Manure produces a small increase in the growth of plants in pots but not as 

 great an increase as is secured from its application in the field. This is probably 

 due to the fact that in the field its effect is mainly due to its physical action. 



"(8) The effect of green manure is negative upon the crop planted immediately 

 after it was applied, but gives a large increase in crops planted subsequently." 



The conclusions drawn from these results are as follows: 



" (1) The soil of the Strongs ville test farm is sufficiently rich in the mineral con- 

 stituents of fertility for abundant crop production, but such is not secured on account 

 of the unfavorable physical condition of the soil. 



" (2) An improvement of the physical condition of the soil, such as is obtained in 

 the process of potting, or by the application of lime, barnyard manure, or green 

 manure, gives a marked increase in the growth of the plants and apparently, to a 

 great measure, obviates the need of the addition of mineral fertilizers." 



Rubber soils, H. X. Ridley (Agr. Bui. Straits and Fed. Malay Slates, 4 {1905), 

 No. 10, pp. 388, 389). — This is a brief note on a circular issued by the Royal Botanic 

 Gardens, Ceylon, which gives a series of analyses of soils and of fresh and decaying 

 leaves, twigs, etc., of the Para rubber plant. These analyses show that in sweeping 

 off the ground 10,000 lbs. of fallen leaves and twigs, about 58 lbs. of lime, 36 lbs. of 

 magnesia, 22 lbs. of potash, and 12 lbs. of phosphoric acid are lost to the soil. 



Behavior of "soluble" phosphoric acid and its movements in the soil, 

 W. Hoffmeister (Das Verhalten der "Vdslichen" Phosphorsdure und ihre Wanderung 

 im Boden. Tnsterburg: Bittnersche Druckerei, 1904; rev. in Centbl. Agr. ('hem., 34 

 (1905), pp. 817-S20; .Tone. Chem. Soc. [London], 90 (1906), No. 520, II, p. 1?0).— 

 The results of 5 years' pot experiments on this subject are reported. Solubility in 

 ammonium humate was used as a means of tracing the variations in the amount and 

 distribution of the assimilable phosphoric acid at different periods. 



The results indicate that long continued culture did not completely exhaust phos- 

 phoric acid soluble in ammonium humate. The reduction in the amount of such 

 phosphoric acid was apparently due to withdrawal by crops and not to reversion to 

 insoluble forms. Notwithstanding the constant removal of phosphoric acid from 

 the subsoil, the relative amount of soluble phosphoric acid was found to increase 

 from the surface downward, indicating a downward movement of the phosphoric 

 acid in the soil. 



