288 



PRINCIPLES AND PRACTICE OF PRUNING 



less productive than the bushes and much more likely to 

 be killed by borers; fpr when the tree is so attacked its 

 one stem is destroyed, whereas when a stem in a bush be- 

 comes infested it may be cut out and burned and the other 

 stems allowed to continue to live and bear fruit. 



The bush form is the popular one, both with people who 

 neglect their plants and those who grow currants for 

 profit (Figs. 250, 251). No matter how badly neglected, 

 some fruit may be expected. Pruning, combined with other 

 rational treatment, will make the plants bear fine fruit 

 abundantly. The flower buds are borne mainly on twigs 



FIG. 246 BLACKBERRY CANES AFTER PRUNING 

 Same as Fig. 245 after thinning out and cutting back. 



of last year's growth and on short annual spurs on wood 

 two or more seasons old. Usually the finest fruit is borne 

 on the young wood, but it is unwise to dispense entirely 

 with older wood. The best practice keeps a constant 

 succession of new canes coming up to replace the old ones. 

 Commercial growers favor six to 12 canes to the bush, 

 two or three new ones being allowed to develop each 

 year, the oldest ones being cut out after having produced 

 two or usually not more than three crops. 



