10 Sept., 1917.] Spiimj Grafting of the Vine. 561 



Fitting or Siock and Scion. 



Of quite equal importance to tiieir proper preparation is the eflScient 

 fitting of tiie judiciously trimmed scion into the stock prepared to receive 

 it. This should be dexterously effected by one single movement, care being 

 observed that the bark is not separated from the wood on either stock 

 or scion, as might easily hapjjen if the assembling of the two were done 

 in a hesitating or clumsy manner. If the stock be large, a small wedge 

 of bone, or some hard wood, may be used to slightly open the cleft at 

 the opposite side to that where the lower bud of the scion will be situated. 

 To facilitate description we may cull this side of both stock and scion 

 the " front "; that opposite to it being referred to as " back." The 

 wedge would thus be inserted at the back of the cleft. With stocks of 

 moderate size — the most usual case — this temporary wedge is unneces- 

 sary ; the apex of the trimmed scion can be easily inserted into the top of 

 the cleft. 



This being done, the scion is pressed home, steadily but hrmly, with 

 the right hand, the fingers of the left hand being used as a guide to 

 ensure tlie barks of stock and scion being level at the front of the graft. 

 The scion must be pressed sufficiently far to entirely fill the cleft, but not 

 far enough to split the stock any deeper than the point to which the 

 knife penetrated when making the cleft. Some variation is permissible 

 in fitting the scion. This may be done as shown in Fig. 1, two small 

 half moons of woody section, one on each side of the scion, being left 

 uncovered. It may, however, be pushed in deeper, so that the scion 

 sections are entirely hidden by the sides of the cleft; for this to be 

 possible, the cuts made when trimming the scion must be absolutely 

 plane sections, without curve or shoulder at the top of the wedge. Sucli 

 latituda is, of course, impossible in the case of a shouldered scion (Fig. 

 2, c & d). What is essential is that the scion should absolutely fill 

 the front of the cleft without any gaps or unfilled spaces. 



The most vital point of all, however, is the proper fitting of the cut 

 surfaces along the front of the graft. Hitherto, for convenience, we 

 have only relerred to the need for bringing tlie barks of stock and scion 

 level. In reality, something more is required, and this must now be 

 expl.ained in detail. It is not the outer, hut the inner, surface of the 

 Ixirlcs, III other u-ords the cainhiitm layers, which must correspond. The 

 vital importance of this tissue was pointed out in the article on the 

 Yema graft (see .Journal for February, 1917). The cambium layer, 

 which everywhere separates bark from wood, is the only portion of the 

 cut surfaces of stock and scion where new tissues can form ; being very 

 thin, the section where it is cut is little more than a line, and these lines 

 on both stock and scion must be in contact in the greatest measure 

 possible; the more completely do they coincide, the more perfect vvill the 

 graft be. Unless thei/ meet in one point at hnxt , no union is possible 

 and the graft must fail. 



Now, in field grafting, the bark of the «tock is nearly always 

 thicker than that of tiie scion ; with stocks planted a year or more before 

 grafting, it may be considerably thicker. It thus follows that the 

 outer surfaces of the bark of stock or scion, in a properly executed 

 cleft graft, will seldom be quite flush ; that of the stock will be slightly 

 sunken in when viewed from the front. The thicker the bark of the 

 stock, the greater the difference of level. A. skilful grafter carefully 

 examined the bark thicknesses of s'^ock and scion and makes allowance 

 accordingly. It is often recommended to slightly cant the scion when 



