76 SCIENCE AND FRUIT GROWING 



the root-growth. As compared with the cut-back trees repre- 

 sented by 100, the weights of new wood formed were 



Branches. Roots. Total new growth. 



40 90 65 



whilst with the pears a similar result, but to a much exaggerated 

 extent, had occurred, the root-formation having actually exceeded 

 that of the cut-back trees, and having been sufficient to more 

 than counterbalance the diminished branch-formation, so that 

 the total of the new wood formed, branches and roots together, 

 was greater with the not-cut-back than with the cut-back trees. 

 The values were 



Branches. Roots. Total. 



65 154 137 



As such results might have been due to some accidental circum- 

 stances, a further examination appeared necessary, and a fresh 

 series of experiments on a more elaborate plan was arranged, 

 some of the cut-back and not-cut back trees being left in the 

 ground for various intervals up to five years before being lifted 

 for examination. Unfortunately the variations in the results 

 obtained were too great to lead to any safe conclusions (XV, 62), 

 and the matter must, therefore, rest for the present on the results 

 of the former experiments, which are nearly unanimously opposed 

 to delaying the cutting back of a young tree till the year after 

 it has been planted, the only partial exception found being that 

 of the pear trees mentioned above. 



PRUNING AT DIFFERENT TIMES. SUMMER PRUNING 1 



Just as in the case of cutting back a tree after it has been 

 transplanted, or of lopping an ailing tree, so as regards the 

 ordinary pruning of a healthy tree, the operation may be done 

 at any time during the dormant season without affecting the 

 result. This was shown in the case of a mixed plantation of 

 one-quarter of an acre in extent, which was divided into three 

 strictly similar sections, the trees in these being pruned in early 

 autumn, mid-winter and spring, respectively : the original 

 cutting back had also been done during these same times 

 of the year. The values of the crops from the three sections 



1 Discussions on summer pruning may be found in Jour. Roy. Hort. Soc.. 

 1908, xxxiii., pp. 487-499, and in Garden Chron., 1907, xli., pp. 400-3, 

 406-7. 



