238 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 



portion of resin and beeswax contained in the material may require 

 variation after the first waxing. Too much beeswax makes a soft wax 

 which melts easily in the sun, running away from its proper position, 

 while if too much resin is used the resulting wax is stiff and brittle and 

 readily cracks. Beeswax is much more expensive than resin, and it is 

 therefore desirable for economy's sake to limit its use. 



It is the practice of some grafters to enclose each stub, after grafting, 

 with a large paper sack, hood or cuff, in order to protect the tender 

 young sprouts from sun, wind or frost. As the sprouts elongate the 

 paper is pulled open at the top to let them through. If the scions are 

 tied in with string this must be cut as soon as they are well started in 

 order that it may not cut into the growing scion. 



Top-grafting at best is not always successful, even with the most 

 experienced operators. Much depends on the condition of the tree at 

 the time of grafting in regard to the activity of the sap, and this cannot 

 be foretold or controlled in many instances. At the same time a skillful 

 operator, especially if he has a sufficient choice of grafting wood, can 

 in most cases top-graft the walnut with fairly uniform results. Even 

 after successful grafting has been done, the young sprouts coming from 

 the scions are extremely susceptible to injury from frost and also from 

 hot winds, and failure somtimes results from these sources. 



These scions which establish a successful union soon commence to 

 grow after grafting, sending out sprouts from one or both buds which 

 grow very rapidly, having at first a very tender, delicate nature. At 

 the same time, the tree itself sends out numerous suckers which must 

 be suppressed to a large extent in order to give the grafts every oppor- 

 tunity for development. Considerable judgment must be exercised in 

 regard to removing the suckers, especially in cases where some or all of 

 the grafts do not grow. If the grafting is entirely unsuccessful, some 

 of the suckers must be allowed to develop in order to permit the tree to 

 carry on its normal functions. If the grafts grow on some of the limbs 

 but not on all, it may be well to leave a few suckers on the limbs where 

 the grafts did not take. Again, it may sometimes be better to leave at 

 least one sucker on a large limb on which only one graft is growing. 

 The main object should be to give the scions every opportunity for de- 

 velopment without allowing suckers to choke them out, while at the same 

 time not depriving the tree too much of an opportunity to produce 

 foliage. After grafting, the trunk and branches of the trees should be 

 painted over with a thick, heavy whitewash as a protection against 

 sunburn. Those stubs in which the grafts do not grow should be kept 

 as carefully waxed as those where successful grafting occurs, inasmuch 

 as the wood is extremely susceptible to decay and must be protected 

 against the same as much as possible. 



