732 EXPEEIMENT STATION EECOED. 



Yields from soils that received a complete fertilizer consisting of 320 lbs. of 

 acid phosphate, 60 lbs. of muriate of potash, and 320 lbs. of nitrate of soda per 

 acre were much more profitable than those from any form of partial fertilizer. 

 When the amount of potash in the complete fertilizer was increased the yield 

 was not increased and the quality was reduced. The substitution of either 

 nitrate or sulphate of potash for the muriate showed a reduction in yield. 

 When the phosphorus in the rotation experiment was increased there was a 

 marked gain in the yield, a gi-eater total yield, and a greater net profit than 

 with any other in the series. The omission of phosphorus reduced tbe increase 

 to the lowest point in the series. The next highest total yield and net profit 

 was by the increased amount of nitrogen. 



Comparing nitrate of soda with sulphate of ammonia as carriers of nitrogen, 

 and again with lime, there was an apparent loss for the sulphate of ammonia 

 in the absence of lime and a gain when lime was added. Nitrogen and phos- 

 phorus were applied as tankage at a disadvantage to both yield and net profit. 

 Barnyard manure used at the rate of 10 tons per acre produced yields to an 

 average value of $5 per ton of manure. Reinforcing the manure with phos- 

 phorus (40 lbs. of floats to the ton of manure) materially increased its effective- 

 ness. The data show that lime was apparently not needed on this soil, as the 

 only plat which showed any decided benefit from lime was the one receiving its 

 nitrogen in sulphate of ammonia. 



A general comparison of the continuous and rotative cropping of tobacco 

 shows that the annual value of all the crops has been smaller in the rotative 

 than in the continuous cropping, because of the much higher acre-value of 

 tobacco than of wheat or clover. " On the unfertilized land the average annual 

 total yields for the two 6-year periods of the test have been 399 and 319 lbs. for 

 the continuously grown tobacco and 576 and 536 lbs. for that grown in rotation, 

 thus showing that a clover sod has produced 177 and 217 lbs. of tobacco per acre 

 during the two periods in excess of that grown on tobacco stubble." 



Tobacco: Influence of fertilizers on composition and quality, J. W. Ames 

 and G. E. Boltz {Ohio Sta. Bui. 285 {1915), pp. 173-209, figs. 6).— This gives 

 lesults of experiments conducted at Germantown, Ohio, on light clay loam in 

 which organic and mineral fertilizers were used in varying combinations and 

 quantities to determine their influence on the composition and quality of the 

 tobacco grown. Data show the amounts of fertilizers used and the resulting 

 yields in wrapper, filler, and trash for 1912, the total average annual yields for 

 a period of six years, the percentage content of carbon-free ash, Ca, Mg, Mn, Na, 

 K, P, total N, nitrate N, nicotin, total S, S as sulphates, and 01 of the resulting 

 crop, and the results of smoking tests in regard to fire-holding capacity, flavor, 

 and aroma. 



The methods which were used in collecting and preparing the samples and in 

 making the chemical determinations are described. 



" The results show that the composition has been modified to a greater or less 

 extent by different fertilizer treatments. The several lots of tobacco have a 

 high ash content. When sodium nitrate is applied there has been, in most in- 

 stances, a decrease in total ash, phosphorus, sulphur, and chlorin. Of the 

 essential elements present, calcium is found in largest amount, followed by 

 nitrogen, potassium, magnesium sulphur, and phosphorus. The addition of lime 

 to the soil has decreased the calcium and increased the magnesium in the 

 tobacco. A complementary relation is found to exist between the calcium and 

 magnesium, when the one is high and the other is low. Tobacco from limed 

 plats, as a rule, contains less phosphorus, potassium, and sulphur than that from 

 unlimed plats. Relatively small amounts of phosphorus are removed by the 

 crop, as compared with other constituents which are regarded as less essential 



