64 POMOLOGY 



of reserve materials. Drinkard's ^ experiments with root- 

 pruning, however, show this practice to be of questionable 

 value, if not injurious. The work was conducted with dwarf 

 trees and may have been unusually severe. While fruit-bud 

 formation was stimulated to a marked degree when the 

 trees were severely root-pruned, the effect on the trees was 

 so devitalizing that the fruit which set and matured was 

 small in quantity and size, and hence the advantages were 

 more than outweighed by the serious results of the treat- 

 ment. When spring pruning was also practiced with the 

 root-pruned trees, the stimulus to fruit-bud formation was 

 generally less pronounced and the trees suffered seriously 

 as in the case above noted. 



58. Ringing. — By the ringing of fruit-trees is meant the 

 operation of removing a ring of bark from the trunk or 

 branches. This is an ancient European practice which has 

 not only been used to increase fruitfulness but also to im- 

 prove the size of fruit, as with the grape. The ring may 

 vary in width but it is usually not over an inch or two, 

 and a half inch will accomplish the desired results as readily. 

 The ring may be removed at any point, usually in late spring 

 or early summer, preferably a little earlier than the time 

 the fruit-buds are beginning to differentiate. In peeling 

 off the bark, the tissues to the cambium are removed and, 

 if this underlying tissue is uninjured and does not dry out, it 

 will immediately begin to form new cells and a cortical layer 

 will be laid down shortly. If the ringing is done before 

 active growth starts in the spring, the chances of new tissue 

 forming are much reduced and bridge-grafting may have 

 to be resorted to if the tree is to be saved, for the callus which 

 is thrown out at the wound will rarely be sufficient entirely 

 to heal the wound. 



Results similar to those obtained by artificial ringing are 



1 Ann. Kept. Va. Poly. Inst. 1913 and 1914. 



