BULLETIN 231] WALNUT CULTURE IN CALIFORNIA. 221 



the bud. The surface of this cut should be smooth and uniform and 

 it is usually made by the experienced operator in one stroke. A split 

 is then made with the knife between the bark and the pith on the longer 

 side of the scion, this split extending nearly down to the bud. It is 

 made nearer the bark than the pith, raising only a thin chip of wood 

 with the bark. For each stock a scion is chosen a little smaller in 

 diameter than the stock, the larger scions being put upon the largest 

 stocks, and vice versa. Fairly large stocks are always desirable, espe- 

 cially in propagating new varieties where grafting wood is scarce, as 

 upon them can be used both large and small scions. The stock should 

 not, however, greatly exceed the scion in size, since in such a case 

 complete healing over may not take place the first year. After split- 

 ting the scion it is inserted upon the split in the stock as shown in 

 Fig. 31 2. In this operation the object is to make as tight a fit as 

 possible, and to so place the scion that the cambium layer or inner 

 bark will come into contact with that of the stock at as many points 

 and as closely as possible. It will be seen in the illustration that in 

 this method of grafting, the cambium of the stock and scion may be in 

 contact upon at least three different surfaces. The grafter should 

 carry along a whetstone and keep his knife blade clean and razor-sharp 

 at all times. 



After placing the scion upon the stock the next operation is that 

 of tying. This consists in wrapping soft cotton twine or raffia fibre 

 tightly about the union of stock and scion in such a way as to hold 

 them firmly together. If raffia is used, it should be soaked in water 

 to make it more pliable. 



The next operation is that of waxing, which consists in thoroughly 

 painting over the stock and scion in the vicinity of the union and also 

 the upper end of the scion with grafting wax. It is better to leave a 

 narrow strip on the back of the stock unwaxed in order that the raffia 

 or twine used for tying may decay more readily, or may, if necessar3 r , 

 be cut at this point. With twine it is especially necessary to cut and 

 loosen it after growth from the scion is well started. 



Various formulae for preparing the wax are in use, but all usually 

 consist essentially in a combination of beeswax and resin in various 

 proportions, to which a little oil or paraffine is added, together with 

 other substances in some cases. The following formula is a good one : 



Resin 4 pounds. 



Beeswax 1 pound. 



Linseed oil 1 pint. 



The resin and beeswax are melted in a kettle and thoroughly mixed 

 with the oil while in a liquid condition. Some use raw and some 

 boiled oil. The former sometimes foams up to a troublesome extent 



