170 THE PRINCIPLES OF PRUNING 



made below or above a twig in order to influence the de- 

 velopment of this twig, or of a larger part of a tree. 



"Notches in the bark under a bud are equivalent to one- 

 third or one-fourth girdle, and can be made as girdles 

 are. The effect of the operation in causing the production 

 of fruit is confined, in this case, to a single bud ; at least a 

 more extended influence on the parts above it is hard to 

 observe, and probably does not exist, as the hindrance to 

 sap movement is very small, and the root is not essentially 

 drawn into participation. If, however, many such notches 

 or partial girdles are made on a twig and following each 

 other closely, as perhaps in the case of following the spiral 

 of the bud positions, the effect must be more and more 

 nearly that of a complete girdle. 



"A notch above a bud into the sap -carry ing wood has a 

 contrary effect, as of a one-third or one-fourth cutting-back, 

 which really is done. If the twig were cut off at the same 

 point, a large number of rapidly-growing woody shoots 

 would be expected, particularly if the cutting-back were 

 done in older wood. The deeper into the sap- carrying 

 tissues the knife advances, the more pronounced must be 

 the result. The crude sap taken up by the root and not 

 directly of use in building tissue, c^in only do the work of 

 fitting for use the stored reserve materials. For these 

 reserve materials, thus set into solution, there is no other 

 outlet than that they be worked up and used in a leaf- 

 bud that had remained dormant or in a newly forming 

 adventitious bud below the notch. However, as soon as 



student should consider in connection with our Section 12) : " Je weniger 

 wir zu sehneiden haben am Baum, desto gesunder bleibt er und desto 

 schoner entwickeln sich die Friichte" (The less we are obliged to cut a 

 tree, the sounder it remains and the finer its fruits develop). This 

 sentence must not be taken to mean that Koopmann would discourage 

 pruning, but that it is the part of wisdom to resort to pruning as little as 

 possible, and yet obtain the desired results. 



The student will find an excellent account of special treatments of pear 

 shoots and spurs in Opoix's "La Culture du Poirier," Paris, 1896. 



