324 EXPERIMENT STATION RECORD. [Vol.35 



by sodium nitrate, and tlie influence on starch content was not very marked. In 

 the green manuring experiments the best results were obtained when the green 

 matter and roots were used together with sodium nitrate. Better results were 

 obtained with green matter and roots together than with green matter or roots 

 used with sodium nitrate. Liming produced generally favorable results in these 

 soils, althougli nitrogen assimilation and the starch content of crops were not 

 markedly influenced. The starch content of potatoes was higher when lime 

 was used alone than when used with a basal fertilizer. 



Pot culture experiments, 1914, J. A. Voelckek (Jour. Roy. Agr. Soc. England, 

 75 (191 i), pp. 306-322, pis. 6; Wohurn Expt. Sta. Rpt. WUf, pp. 23^9, pis. 6; 

 abs. in Jour. Bd. Agr. [London], 22 {.1915), No. If, pp. 353, 35.) ) .—Experiments 

 on the influence of sulphate, phosphate, carbonate, nitrate, and arsenite of cop- 

 per on wheat in a relatively rich soil are reported. The results are taken to 

 indicate that sulphate of copper has an injurious effect when used in a quantity 

 supplying 0.05 per cent of copper or more, but that 0.02 per cent of copper or less 

 can safely be used in this form and has a slightly stimulating effect. Phosphate 

 of copper has a generally stimulating influence and can be used in quantities 

 supplying up to 0.1 per cent of copper without producing any toxic effect on 

 the plant. Carbonate of copper is nearly as harmful as sulphate of copper 

 when used in quantities approaching 0.1 per cent of copper. With 0.05 per cent 

 the effect is doubtful, but 0.02 per cent or less has. when used in the form of 

 carbonate, a stimulating influence. Nitrate of copper when supplying 0.02 per 

 cent of copper or more is distinctly harmful, but when used in less amounts has 

 a stimulating influence. Arsenite of copper is very harmful, and even so small 

 a quantity as 0.05 per cent of copper in this form may be toxic in its eifects. 



p]xperiments on the influence of the phosphate, carbonate, nitrate, sulphate, 

 and chlorid of lead on wlieat showed that " in no case was there any sign of 

 injury, although lead had been used up to 0.1 per cent. The general result was 

 to point, on the whole, to a stimulating effect rather than the reverse. This 

 was especially marked with the phosphate series and the nitrate one. With 

 the carbonate and sulphate the results were very similar to the untreated and 

 with the chlorid the straw seemed to be somewhat reduced. . . . Therefore, 

 lead can be used with impunity up to 0.1 per cent with any of the salts 

 employed." 



Experiments on the effects of adding lime to a soil rich in magnesia showed 

 " that addition of lime to a soil rich in magnesia is beneficial and can be ap- 

 plied without detriment even to an extent where the lime is double the amount 

 of magnesia present in the soil." 



Soil-acidity experiments on soil continuously cropped to barley led to the 

 conclusion " that where soil acidity has gone to the extent that a crop can not 

 be produced, lime as carbonate of lime may advantageously be added to an 

 extent exceeding that required to neutralize the acidity present, but that where 

 acidity may be indicated but a fair crop be still produced, there is no advan- 

 tage from adding lime as carbonate of lime even to the neutralizing point. 

 Lastly, when no acidity is shown, further liming is thrown away." In no case 

 did the use of calcium carbonate produce the harmful effects produced by 

 caustic lime. 



Experiments with mustard, barley, peas, and tomatoes to determine the in- 

 fluence of inoculating soil with Bottomley's peat preparation led to the con- 

 clusion that " the peat preparation exercised a distinct influence upon the 

 vegetation. The results with barley, peas, and mustard, coupled with those on 

 the vegetative growth of the tomatoes, clearly show that there is something 

 elTected by the peat and that this is due not to the chemical composition alone." 



