66 PROPAGATION OF PLANTS BY DIVISION 



were improperly named or because the fruit does not suit the 

 market. (2) The orchardist may desire to try some new variety on 

 a tree of bearing age and bring it to fruitage more quickly than if 

 it were worked on young stock. (3) The grower may wish to intro- 

 duce into a block of trees in his orchard a few rows of any desired 

 variety for the purpose of aiding in the cross-pollination of the trees. 



Top-working is done chiefly by three methods : cleft grafting, 

 tongue grafting, and budding. Still other methods are occasionally 

 found but are less common ; for example, side grafting consists in 

 inserting a wedge-shaped scion beneath a very large stem or trunk. 



Cleft grafting was formerly the most common method of top- 



FIG. 57. Students setting out rooting grafts .in garden rows. Note the completed row at 

 the right. (New Jersey Station.) 



working orchard trees. Limbs varying in size from one-half to 

 two inches in diameter are cut square across with a saw. With a 

 chisel or special grafting cleaver, the end is split to receive two 

 scions bearing the buds of the desired variety. The scions are cut 

 in a wedge-shape form, one being inserted near the cambium layer 

 at one edge, and one at the other, of the split stem. The scions 

 should be slightly beveled to make them fit the stock most perfectly 

 at the cambium layer and bark. The wounded surfaces are then 

 thoroughly covered with grafting wax to protect them from the 

 weather. This operation may be performed at any time during 

 the early part of the growing season, dormant scions being used. 



