442 STATE BOARD OF AGRICULTURE. 



TOP WORKING APPLE TREES. 



Circular No. 14. 



When a bearing orchard contains undesirable varieties and the trees 

 are sound and healthv, it is often advisable to top-work them. This 

 consists of grafting the branches with scions of a more desirable variety 

 and thus changing the entire bearing surface of tlie tree into a different 

 variety. i , , 



Selection of Scioiis. Scions (Fig. 2A.) are selected from bearing trees 

 of the desired variety. They are cut preferably in late fall or early 

 winter although they may be cut any time before the buds swell in 

 the spring. Only wood from bearing branches of the past season's 

 growth is selected and after cutting them into lengths of eight to twelve 

 inches, they are plainly labeled and tied into bunches of convenient 

 size. They should then be i^acked in sand or sawdust and stored in 

 a cool cellar or some place to prevent them from starting into growth 

 before grafting. 



Time to graft. The trees may be grafted any time in the spring be- 

 fore the sap begins to flow. It is generally performed about the time 

 the trees are ordinarily pruned in the spring. If the trees are not 

 grafted at this time and the scions are kept dormant in some cool place 

 as an ice house, the grafting may be successfully done later in the spring 

 when pruning may be performed without serious bleeding. 



The most imjjortant factor in top-working large trees is the selection 

 of the branches to form the top. Scions when grafted upon horizontal 

 branches, instead of continuing to grow in the direction of the original 

 branch, always grow upward. This tends to produce a narrow high- 

 topped tree. Great care should be exercised, therefore, in selecting 

 branches well away from the trunk and covering all the fruit-bearing 

 surface of the tree. The branches should not exceed an inch and a half 

 in diameter at the point of graftage as scions seem to prove more suc- 

 cessful on branches of this size. In top-working an old tree about one- 

 third of the branches that are to be grafted should be worked each 

 year as the cutting of more branches in a single season would prove too 

 severe. It will, therefore, take three to five years to renew the entire 

 top. Where the fruit bearing surface is large, this will often necessitate 

 the making of ten to twenty grafts each season for about three suc- 

 cessive years. All the important branches should be grafted, and it 

 is safer to graft too many branches and be obliged to cut out a few in 

 later years than not to graft enough. 



How to Make the Graft. In top-working mature trees, the cleft graft 

 is the form generally used. 



With a pruning saw, a branch an inch to an inch and a half in diame- 

 ter is cut, being careful not to loosen or tear the bark on the stub. If 

 the saw is coarse, the stub may be dressed with a sharp knife which will 

 tend to hasten the callousing. A grafting tool as shown in Fig. 1 may 



