320 . EXPEEIMENT STATION RECOED. 



experimeuts at the Ohio Station contained in an article by Warren, previously- 

 noted (E. S. R.. 29, p. 213). 



Further notes on interpreting fertilizer tests, G. F". Waeben {Jour. Amer. 

 fioc. Agron., 5 (1913), No. 3, pp. 137-140). — A reply to the article noted above 

 reiterating certain points emphasized in the previous articles, viz, that in fer- 

 tilizer experiments "(1) more attention should be given to the place in the 

 rotation at which fertilizers are applied. (2) The difference between the cost 

 of a fertilizer and the value of the increased crop is not all profit. The extra 

 cost of harvesting, storing, and marketing increased crops must also be con- 

 sidered, particularly in cases where a very expensive treatment gives only 

 slightly greater returns above fertilizer cost than is given by a cheaixjr treat- 

 ment. (3) Too little attention is given to the inceased value of the land 

 because of the residual effect of fertilizer.s." 



Fertilizing the rotation, H. O. Buckman (Jour. Amer. Soc. Agron., 5 (1913), 

 No. 3, pp. 157-164)- — Conclusions regarding the time and manner of fertilizing 

 a rotation are drawn from data derived from various sources. 



Stimulants of plant growth (Rev. 8ci. [Pari,<<], 52 (1914), I, No. 21, p. 663).— 

 This is a brief note referring to the use by Payen in 1S37 of the term " stimu- 

 lant " as applied to certain kinds of fertilizing materials now frequently referred 

 to as catalytic. 



The fertilizing value of the above-ground paiiis of cereals and leguminous 

 plants, J. MiKULOwsKi-PoMOKSKi (Kofimos [Lemherg], .38 (1913), pp. 929- 

 951). — From the large amount of data bearing upon this subject which are 

 reporte<l the conclusion is drawn that the greater value of leguminous plants 

 for green manuring as comparefl with cereals is due not only to the ability of 

 the former to utilize the free nitrogen of the air but also to the fact that the 

 nitrogen which leguminous plants contain is qualitatively of greater fertilizing 

 value than that of cereals. This is true not only of the stems and leaves but 

 also of the seed. 



The nitrogen of Graminei^ in the earlier stages of growth is of greater fer- 

 tilizing value than that of the maturer plants. The fertilizing value decreases 

 as the plants approach maturity. Thoroughly ripe straw may even be in- 

 jurious. Such marked changes were not observed in the leguminous plants as 

 they matured. The nitrogen of the seed of legtiminous plants was of greater 

 fertilizing value than that of the stems and leaves. 



The changes of stable manure during storage and its action in soil, F. 

 LoHNis and J. II. Smith (FilliUng's Landw. Ztg., 63 (1914), ^o. 5, pp. 153- 

 167). — Experiments with fresh stable manure and manure in different stages 

 of decay to determine (1) the numbers and kinds of organisms present. (2) 

 the qualitative and quantitative changes undergone by the solid and liquid 

 constituents when separated and combined, particularly as regards the nitrogen 

 content, and (3) the extent of the activity in soil of the nitrogen content are 

 reported. 



The residts indicate the importance of preventing the great losses of nitrogen 

 in manure during storage and in distribution and of better utilizing the 

 plant food content. The following conclusions are drawn : Urine may be mixed 

 with peat dust and used in that form, thus decreasing the loss of nitrogen 

 through ammonia evaporation. Excrement and straw mixture and urine when 

 use<l separately have a better effect and suffer less loss in value. The chief 

 value of excrement and straw mixtvu-e lies in its high bacterial content and Its 

 richness in humus-forming organic matter. Its fertilizing value is always small 

 and in the most favorable cases the nitrogen action can increase only about 20 

 per cent in the first year. About one-half of the excrement nitrogen is present 

 in the form of living and dead microbes, the other part being derived from the 



