10 MASS. EXPERIMENT STATION BULLETIN 327 



Row Application Broadcast Application (Check) 



Pounds Pounds 



per Acre per Acres 



% Standard amount 1874 Standard amount 2128 



Y$ Standard amount 1708 Standard amount 1994 



Y<l Standard amount 1743 Standard amount 2086 



During the years 1932 and 1933 the relative yields of tobacco were better 

 when the fertilizer was placed in the row than when it was broadcast. Approx- 

 imately 5 , s the amount, when applied in the row, was equivalent to the full 

 amount broadcast. However, during the last two years, 1934 and 1935, the 

 favorable effect of row application has not continued. It seems that the 

 residual effects of fertilizer applied broadcast in previous years has overcome 

 this seeming advantage. 



Proportion of Organic Nitrogen. Varying amounts of cottonseed meal as a 

 source of nitrogen for tobacco were used in field trials and the relative yields 

 were as follows: 



Pounds 

 per Acre 



Check (regular tobacco mixture) 2330 



Y% N from cottonseed meal 2291 



\i N from cottonseed meal 2152 



Y% N from cottonseed meal 2193 



1 2 N from cottonseed meal 2221 



Form of Nitrogen. This experiment was planned to determine which form 

 of nitrogen is most valuable from the standpoint not only of yield but of the 

 production of good quality in tobacco. One half of the nitrogen was supplied 

 from cottonseed meal and the other half from the following materials. The 

 yields show no marked differences. 



Pounds 

 per Acre 



Check (regular tobacco mixture).' 1910 



14 N from nitrate of soda 1967 



y% N from sulfate of ammonia 1925 



'•j N from calcium cyanamid 1859 



1 •_> N from urea 1895 



Distribution of Nitrogen in Soils Mixed with Different Plant Tissues 

 and Allowed to React for Two Months. (W. S. Eisenmenger. ) Tobacco 

 planted in rotation with corn or timothy is frequently affected by brown root- 

 rot during certain seasons. Experiments at other stations show favorable 

 results when tobacco follows ragweed, horseweed, or tobacco. An attempt was 

 made in the laboratory to learn whether the manner in which these various 

 tissues break down would show any reason for the effect which they produce 

 on tobacco. 



Ground tissue from each of the plants -■- tobacco, horseweed, ragweed, 

 timothy, red top, and corn — was mixed with soil in crocks, in amounts to 

 keep the nitrogen equal. At the end of eight weeks those soils containing 

 vegetative tissues of red top, timothy, and corn contained more carbon than 

 did the soils containing tissues from tobacco, ragweed, and horseweed. 



It has been the experience in our laboratory that those plant tissues which 

 are slow in losing carbon when mixed with soil are also slow in ammonifying 

 and nitrifying. 



