STUDIES ON THE CURING OF LEAF TOBACCO. 7 



sample (1908) the loss would undoubtedly have been considerably 

 greater had the stems been permitted to cure, as is to be expected, 

 because of the relatively high starch content in this sample. For 

 the types of leaf considered, the average loss in weight in dry matter 

 during the curing of the picked leaves may be placed at about 12 to 

 15 per cent. 



The data presented in Table I, section A, relate only to types of 

 tobacco adapted to and grown under conditions favorable to the 

 production of cigar-wrapper leaf, which is relatively very thin and 

 light. This class of tobacco is harvested in a less ripe condition 

 than are other classes of leaf, so that a lower content of starch is to 

 be expected in the leaves when harvested. For these reasons the 

 loss in dry weight in curing is greater in other classes of tobacco, and 

 in the case of the export types losses in weight as high as 38 to 40 

 per cent have been observed. The loss in weight in curing varies with 

 the variety or type grown, the conditions under which the tobacco 

 is grown, the degree of ripeness when it is harvested, and also with 

 the conditions under which the curing takes place. The effects of 

 these factors on the loss in weight are due to their influence on the 

 composition of the leaf before or after the curing, particularly on 

 the content of starch. 



LOSS IN WEIGHT OF DRY MATTER IN AIR CURING WHEN THE LEAF 

 IS CURED ON THE STALK. 



The experiments relating to the loss in weight when the leaves are 

 cured on the stalk cover the crop years of 1908 to 1910, inclusive, 

 a period of three years, and the experimental material was obtained 

 from the same fields as was that used in the preceding experiments. 

 The stalks of the plants used were not split in harvesting, but were 

 hung in the barn in the usual manner for curing cigar tobaccos. 

 Every effort was made to have the experimental material directly 

 comparable with that used in the preceding experiments for the 

 same years. Plants were selected which were as nearly as possible 

 like those used for the experiments in priming. Beginning near the 

 base of the plant each alternate leaf was picked off, taking three or 

 four leaves from each plant and leaving all of the remaining leaves 

 intact. The stalks were then harvested and placed in the barn for 

 curing. The midribs were promptly removed from the picked leaves 

 and both the leaf web and the midribs completely dried, as in the 

 previous experiment. The dry weights of the leaf parts were recorded 

 and the material preserved for analysis. When the leaves attached 

 to the stalks were cured the weights of the leaf web and midribs were 

 likewise obtained and the material kept for further examination. 

 As in the case of the experiments in priming, the leaves were removed 

 from the stalks in the 1908 experiment before the midribs were 

 fully cured. With the possible exception of the 1909 material, the 



