108 PRINCIPLES AND PRACTICE OF PRUNING 



and in what degree, if at all, the operation induces and stimulates 

 fruitfulness. 



Ringing should be performed early in June or July, at which time 

 the bark peels readily frorn the wood, leaving the cambium in a 

 succulent condition. The success of the operation hinges upon the 

 fact that at this season occurs the greatest cambial activity, which 

 readily facilitates the rapid formation of new bark, and at the 

 same time prevents exhaustive evaporation of plant juices. Any 

 attempt to practice ringing when plant growth is sluggish or dor- 

 mant always results in the death of the tree, since the cambium, 

 being then firm, is torn from the woody cylinder during the opera- 

 tion. A common pruning knife (Fig. 112) or a sharp pocketknife 

 js a suitable instrument for performing the operation. 



From the data secured, it would appear that ringing tends to 

 ha*'* injurious effects upon apple trees, and that the wider the 



FIG. 74 EFFECTS OF RINGING YOUNG TREES 



1. One-inch ring of bark freshly removed from apple tree. 2. New bark over 

 1-inch ring. 3. New bark over 3-inch ring. 



bands the more serious will be the injury. It may be stated that 

 the trees used were exceptionally strong and uniform in vigor and 

 were therefore possibly in a better condition to withstand wounding 

 than are average orchard trees. All of the trees making a weak 

 growth showed smaller foliage and less wood production. The 

 foliage, likewise, lost its color and fell from the branches four to 

 six weeks earlier than that of normal trees. Two to six sprouts 

 sprang up at the. lower edge of the wound on nearly every tree. 

 This would indicate that nature was endeavoring to provide as 

 similated food for the roots since passage of such food from the 

 upper portion of the trees had been cut off. 



No gain in productiveness resulted from ringing. The few 

 fruits which were produced showed no differences in size or color 



