THE TREATMENT OF THE*SHOOT 155 



also advisable to cut a branch with a sharp knife, and in the 

 case of thick branches, to pass over the sawn surface, at least 

 at the margin, with a knife. If the surface is very rough, so 

 that the injured and dying cells terminate at diiferent heights, 

 the atmospheric moisture remains in contact with it for a 

 long time and in considerable amount, and offers facilities for 

 the spores of parasitic Fungi to lodge themselves on the surface 

 and to germinate there. In large wounds, which take many 

 years to cover, it is necessary to protect the wounded surface 

 from atmospheric influences. Of all the substances used for 

 this purpose, those should be preferred which produce the 

 same effect that is produced by natural means in the case of 

 Conifers. But as the resinous substances used for this purpose 

 are still too expensive for universal application, tar is most 

 generally used. On account of the cracks, however, which 

 gradually appear in an old wound which has remained open, 

 it is advisable to repeat the tarring. 



§ 32. By what means can we increase the effect of pruning? 



We do not always attain by pruning the end we have in 

 view, and this is especially the case when we seek to accelerate 

 or augment the productiveness of our trees. In consequence 

 of this failure, recourse is often had to operations the nature 

 of which we will now examine. 



(a.) The Sending of Shoots. 



The operation which gives least irritation to the economy of 

 the plant is the bending of shoots. 



In most cases where these artificial means are employed, 

 branches are bent from a more or less vertical towards a more 

 horizontal position. From our preceding considerations we 

 know the effect of this procedure. First of all, the nutritive 

 sap becomes unevenly distributed. In their natural position 

 the water supply is most favourable to the buds near the apex 

 of the shoot. If the shoot is bent, however, so that the apex 



