BLACK ROOT-ROT OP" TOBACCO 125 



good without lime as witii lime; but in the otlier three comparisons, burn was 

 of longer duration with lime tiian without it. The differences were not great, 

 and the only conclusion is that the burn of the tobacco of 1925 was not con- 

 sistently better or worse in limed plots than in plots not limed. 



From Table 11 it is seen that the burn of the crop of 1926 was somewhat 

 better with lime (Plots 12 and 21) than without it (Plots 5 and 17). The in- 

 creases in fire-holding capacity on limed plots were 15 per cent in the medi- 

 ums, 24 per cent in the seconds, and 61 per cent in the darks. 



In 1927^ however, liming did not consistently improve the burn. Lime 

 was associated with a better burn of the seconds on one plot (Plot 24) but 

 not on its duplicate (Plot 12), and in three out of four possible comparisons 

 Ume did not improve the burn of the darks. (Table 12.) 



The fire-holding capacity of the crop of 1928, the year of the rainiest 

 growing season, was very good on the whole, and the burn of both darks and 

 seconds from plots not limed was as good as or better than the bui-n of the 

 corresponding leaves from limed plots. (Table 13.) 



In 1929 seconds from limed plots 12 and 24 held lire slightly longer 

 (mean of 29 seconds) than did leaves of this grade from pilots 5, 6, 17, and 18, 

 not limed, (mean of 26 seconds) ; but darks from the limed plots did not hold 

 lire quite as long (mean of 16 seconds) as did darks from the unUmed plots 

 (mean of 18 seconds). The differences are small and inconsistent and shov>- 

 only that liming was without significant effect on burn in 1929. (Table 14.) 



In four out of these six years lime in the amounts applied to this soil did 

 not improve burn of the leaf; that is, it did not increase the fire-holding 

 capacity as determined by strip tests. In only two years, 1924 and 1926, did 

 lime unprove burn. 



These results are in general agreement with those presented in the liter- 

 ature on this subject. In the experiments of Ames and Boltz (1), tiie ap- 

 plication of lime to the soil shortened the time of burning of tobacco. Accord- 

 ing to Haley (18), lime does not improve the combustion of cigar leaf to any 

 extent and if applied in large quantities it may injure burn. Garner (16) 

 has reported that lime does not much aft'ect the fire-holding capacity of to- 

 bacco. Lime reduced the fire-holding caj)acity of tobacco in strip tests, but 

 not in cigar tests, in Connecticut (6). 



Considering only unlimed jilots 5 and 17, the best burn of these four 

 years was in the rainiest season and the poorest burn was in the dryest sea- 

 son. The differences were greater than those associated with lime or no-lime 

 treatments of the soil. 



Year Rainfall Length of burn in seconds 



(June, July, Aug.) (Unlimed Plots 5 and 17) 



Darks Seconds 



1926 9.25 6 9 



1927 11.78 13 13 



1928 21.60 41 25 



1929 12.11 13 20 



Effects of Tobacco, Alfalfa, Timothy, and Alsike Clover 



On Soil Reaction and Remoz'ul of Lime in the Crops 



The number of pounds of calcium and magnesium oxides removed in 

 each of these crops from each plot in 1926, 1927, and 1928 is recorded in 

 Table 5. 



