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ticed, there was practically no difference. Cutting the leader of the 

 main shoot or pruning the laterals caused an increase in the number 

 of laterals. Where laterals are not cut, they are not formed as a rule 

 in the axil of every leaf. Pruning causes a larger amount of fruit to 

 set in the first axils of the laterals, as it was found that in the exper- 

 iment were pruning was practiced 91 per cent of the axils produced 

 fruit, against 55 per cent where no pruning took place. In some 

 instances where the leader was nipped on unpruned plants, this 

 resulted in causing a slight increase in the amount of fruit in the first 

 axil of the laterals. 



In conclusion it may be stated that from our experience the advan- 

 tages of pruning seem to be an increase in the yield of fruit, and a 

 concentration of fruit on the plant. 



Physiology of Pruning. 



One of the fundamental properties of protoplasm is irritability or its 

 capacity to respond to stimuli. Light, heat, electricity, gravity, etc. act 

 as stimuli, and these cosmic forces exert a profound influence on plants. 

 Mutilation of any sort applied to a plant acts as a stimulus, which 

 gives rise to a series of reactions or responses on the part of the 

 ^organism. The nature of the response is dependent upon the nature 

 and intensity of the stimulus applied. The manner of applying 

 stimuli and the nature of the organs stimulated also exert an influence 

 on the mode of reaction. In general, when secondary organs 

 (branches, etc.) are cut, there are manifested important changes in 

 the behavior of the primary organs (stem, etc.); and, conversely, 

 when the primary organs are cut, changes take place in the charac- 

 teristic behavior of secondary organs. The cutting of branches 

 causes an elongation of the stem, and when the apex of the stem is 

 decapitated there occurs an elongation of the branches. Similar 

 phenomena occur in all plants, but these correlated growth changes 

 are by no means the only ones that occur as a result of pruning. 

 Indeed the variety of responses due to pruning which occurs in 

 economic plants is quite numerous. Modifications of the fruit and 

 the production of supernumerary structures may take place. In 

 short, the mutilation of any portion of the plant affects the whole 

 organism, the greatest effect occurring nearest the point of mutila- 

 tion, as is illustrated in the production of new leaders and in the 



