MODIFICATION OF SIZE OF LEAVES. 29 



purposes, and this may be accomplished with no additional expense 

 to the grower. 



The shape of the leaf in certain types of smoking tobacco largely 

 determines its adaptability, to both soil and market conditions. In 

 Maryland it has been found generally true that a broad leaf gives 

 best results on very light sandy soil, and is best adapted to the 

 demands of the German market, while a somewhat narrower or 

 longer leaf is more desirable on heavy clay soil; from this latter 

 type the highest grades of red tobacco are produced to meet the 

 requirements of the markets of France. In the case of Maryland 

 tobaccos the shape of leaf is usually correlated with the number of 

 leaves, there being more leaves to the plant where they are narrow 

 than in cases where they are broad. The writers have observed many 

 exceptions to this rule and have found that by keeping this point in 

 mind when selecting seed plants it is jDOSsible to find round-leaved 

 plants producing a large number of leaves, and to procure varieties 

 from these plants which will produce a large number of uniform 

 leaves and at the same time a grade of tobacco which will be adapted 

 to the demands of the market for which it is grown. 



It is within the power of the tobacco grower to produce the shape 

 of leaf best adapted to the purposes for which his tobacco is grown, 

 and to continually improve the shape and gradually bring it up to 

 the ideal of a perfectly shaped leaf, by carefully selecting seed 

 plants year after year which produce leaves most nearty approach- 

 ing this ideal. In all cases if uniform types are to be produced 

 cross-pollination must be prevented, in order that the progeny the 

 following year may inherit only the characters of the desirable 

 parent plants. 



THE MODIFICATION OF THE SIZE OF LEAVES. 



The modification and control of the size of tobacco leaves is of 

 almost equal importance to the improvement of their shape, and 

 the size is so intimately associated with the shape that both features 

 can be dealt with along the same lines in the improvement of 

 tobacco by breeding and seed selection. 



The purpose for which the crop is grown must always determine 

 the most desirable shape and size of the leaf, and the individual 

 grower must decide for himself what size and shape will be best 

 adapted to the local market demands. The importance of producing 

 a comparatively definite and uniform size of leaf is well recognized 

 by the manufacturers of all classes of tobacco. In the case of the 

 Maryland Smoking tobacco grown for export purposes it is difficult 

 to procure a leaf which is too large for the highest market demands, 

 especially when it is grown for the French market. In most cases 



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