132 EXPERIMENT STATION EECOKD. 



acidity upon plant growth. . . . The injurious effect of sulphate of ammonia 

 upon the soil . . . can be entirely overcome by the application of sufficient lime, 

 as indicated by pot experiment." 



A review of the work of others bearing on the subject and a bibliography of 

 related work are also given. A description and discussion of the analytical 

 methods employed, including a modified Veitch method for determining the lime 

 requirement of soil, are appended. 



The influence of lime on the yield of dry matter and percentage of nitrogen, 

 J. G. LiPMAX, A. AV. Blaib, H. C. McLean, and L. K. Wilkins {Xeic Jersey 

 Stas. Rpt. 1914, pp. 236-238, pi. 1). — Pot experiments with crimson clover on 

 an acid sandy loam soil containing .some gravel, to which ground limestone was 

 added at the rates of 10, 25, 50, and 100 gm., and sodium nitrate at the rate of 

 2 gm., per 18 lbs. of soil showed that " in all cases where lime was used the 

 average yield of dry matter is at least 10 gm. more than where no lime was used. 

 The difference in yield with 10 gm. and 100 gm. of limestone is not great, the 

 highest yield being with 25 gm. Also the yield is higher with 2 gm. of nitrate 

 of soda than on the check. The percentage of nitrogen is likewise distinctly 

 higher with lime than without." 



With a residual crop of soy beans it was found that the yield of dry matter 

 from the limed pots Avas more than double that from the unlimed pots, while the 

 nitrate of soda pots yielded less than the untreated pots. The percentage of 

 nitrogen in the crop, while not so high as in the preceding crop, was still higher 

 in the limed than in the unliniod pots. 



The effect of large applications of ground limestone on the yield and 

 nitrogen content of dry matter, J. G. Lipman, A. W. Blaib, H. C. McLean, 

 and L. K. "Wilkins {New Jersey Stas. Rpt. 191. 'i, pp. 23S-2.'fO). — Pot experi- 

 ments with barley, similar to the above, in which ground limestone was addeil at 

 the rates of 10, 81.7, 103.4, 40S.6, and 817.2 giu., and sodium nitrate at the rate 

 of 2 gm., per from 16 to 18 lbs. of soil .showed that "applications of limestone 

 ranging from 1 to 10 per cent gave yields of dry matter which are more than 

 double the yield without limestone and slightly in excess of the yield with nitrate 

 of soda. . . . With applications of limestone the percentage of nitrogen in the 

 dry matter was not so high as with nitrate of soda, but somewhat higher, on the 

 average, than without limestone." 



Besults of thirty years of liming, W. H. McInttbe (Pennsylvania Sta. Rpt. 

 1912, pp. GJf-lo). — Field experiments with burnt lime with and witliout manure, 

 ground limestone, and gj-psum on a silty clay loam soil are reportetl. the purpose 

 being to ascertain (1) to what extent and depth applied lime descends into the 

 subsoil, (2) the amount of lime consorvetl and lost by cropping and leaching, and 

 (3) the effect of lime upon the chemical composition of the soil. The crops 

 grown were corn, oats, wheat, and grass. Burnt lime and ground limestone were 

 applied at the rate of 4,000 lbs. per acre, gj-psum at the rate of 320 lbs. per acre, 

 and manure at the rate of G tons per acre. 



Where lime was applied alone increased crop yields were obtainetl only with 

 ground limestone. Burnt lime decreaseil the organic matter of the .«!oll when 

 applied alone and decreased humus accumulation when applietl with manure. 

 Calcium sulphate and ground limestone increaswl the organic matter. Each 

 form of lime increased the nitrogen content of the soil, gj-psum, limestone, and 

 burnt lime being effective in the order given. The addition of lime to manure 

 increased crop yields and the nitrogen content of the soil. More lime was 

 removed from the surface in the case of ground limestone and when lime was 

 used with manure than when burnt lime was uso<l alone. :^Lanure induced more 

 thorough dissemination of lime throughout the entire 21 in. of soil, at the same 

 time conserving it. 



